Dark Side
by starlabsforever
Summary: Cisco is afraid that he'll turn into Reverb, and maybe he's right to be afraid. He used to believe that he would never give in to Cloud City Vader, but he's not so sure anymore. As he realizes what he's capable of, he drifts further away from the morality he knows. The only thing keeping him tethered to the ground is Caitlin.
1. Chapter 1

**A/N: Takes place after 3x07 but before 3x08.**

* * *

 _It's dark and cold, colder than I was before. It only takes me a moment to realize where- and when- I am._

 _August 9th, 2016. Roughly 8:30 PM._

 _I'm standing on the side of the highway, as usual. The road is dark, lit only by the headlights of passing cars. I watch the oncoming stream of traffic, waiting for his car to appear._

 _There it is. That lame 2004 Volvo he loved to drive around. He was so proud of that car, because it was the only thing he ever bought with his own money._

 _Why is he going so damn fast? He's obviously not paying attention to where he's going._

 _He was never a good driver. Only reason he passed the test was because the Driver's Ed instructor was in love with him. He was too arrogant to ever be a good driver._

 _Come on, Dante, look where you're going..._

 _There it is. That stupid blue 2010 Wrangler. Who buys a blue Jeep, anyway?_

 _Slow down, you moron! Is he on his phone? If you would just look up for one second-_

 _Oh jeez, I can see his face. That's new. He won't even know what hit him if he doesn't look up-_

 _He looked up. Just too late. He looks so scared._

* * *

Cisco woke up with a shudder. He felt his whole body trembling with adrenaline and repressed emotion. _What time is it?_ He fumbled for his phone on the dresser beside him and tapped the power button.

3:51 AM. _That's even earlier than last night. Damn it, I'm so tired._ But there was no way he would be able to go back to sleep now. He was never able to sleep after that dream.

Except this time it didn't quite feel like a dream. This time it had felt a hell of a lot more real. He had known he was cold, for instance. He had felt the other cars rushing by him. And this time, he had seen Dante's face. That had been too much for him.

Cisco rolled over onto his side and groaned. The post-nightmare splitting migraine had settled in. Dreaming about his dead brother was enough to make him want to stay in bed all day, but the headache that felt like thirty nails being pounded into his skull was just the icing on the nightmarish cake. This had been going on for two weeks now- the same dream waking him in the middle of the night, and every night it got earlier. He hadn't been able to bring himself to get in bed until after midnight, and a couple restless hours later the nightmare had yanked him awake. He didn't know how he was going to make it through work today. _Not that anyone will notice._ If Caitlin or Barry had noticed his sleep deprivation, they didn't care. Life at S.T.A.R. Labs was even more chaotic than ever, with Alchemy on the rise, and Caitlin and Barry had been so preoccupied with fighting metas that they hadn't even noticed when he blacked out twice the other day.

He swung his legs over the side of the bed, forcing himself to stand up. His legs felt weak beneath him and then gave. He fell to his knees and let out a weak moan. His body was still trembling.

All he wanted was to sleep. Stupid dream.

And why wouldn't his hands stop shaking? He stared at them in disgust, trying to control the violent shaking, but the vibration only seemed to intensify-

Hang on. Vibration.

 _Vibe._

"You idiot," he whispered, and staggered to his feet. Of course. Why hadn't he seen this before? He hadn't been dreaming about Dante. He'd been Vibing. That explained the weird realism of the dream, the lack of sleep- and the shaking. _How did I not realize that? I know what a Vibe feels like._

Was it possible to Vibe to the past? He'd never done it before. Sure, he'd Vibed himself and Iris into the speed force once, but that was different. It wasn't exactly the past. And even if he could Vibe to the past, why would he do it subconsciously? Or how, for that matter?

He glanced at his phone and considered calling Caitlin. This was a Vibe thing, so that meant it was okay to call her at 4 in the morning, right? It was a work emergency. Really, the reason he wanted to call her was because he was tired and lonely as hell and he needed someone to talk to. But that was selfish reasoning. _Let her sleep._ Which was ironic because he was the one who could barely get to sleep when Caitlin probably slept eight hours a night. Still, he couldn't bring himself to wake her up.

He walked shakily to his bathroom door and splashed some cold water on his face, but it didn't make him feel any more awake. He stared at his reflection in the mirror, appraising himself. _I look awful._ He looked pale and washed out, which only made the shadows under his eyes more pronounced. This was what two weeks of not sleeping did to you.

He thought about going downstairs to work out, but he felt so weak and fatigued that he didn't think he could make it down the stairs. He stumbled back over to his bed and collapsed on top of the covers.

* * *

The rattling of the subway was driving him crazy. He felt like his head was going to implode. He reached for the headphones hanging around his neck and slid them over his ears, attempting to drown out the sound.

He hadn't slept at all that morning, just laid on his bed for three hours trying to force himself to stop thinking, but his body was on fire with vibrations. And he couldn't stop thinking about Dante. The horrified look on his face when he finally realized he was in danger- that had just brought back all his grief over his brother all over again.

He brought one of his hands up to his face and studied it. It was tremoring so quickly that if he stared at it long enough, it didn't even look like it was moving.

His powers had never been out of control like this, not since he'd first discovered them. There was still a lot he didn't know how to do, and sure, there had been times when he felt like his mind was being barraged by Vibes- but he'd never felt like a live wire before.

The train came screeching to a halt and his body lurched forward. He barely caught himself before faceplanting on the ground. He awkwardly stumbled to his feet and out the door, ignoring the stares he'd attracted. The noises of the train station felt like a jackhammer in his brain, so he turned the volume of his music up louder.

Whatever was going on with his powers, it probably wasn't a big deal. It probably felt worse than it was because he was tired. _But you're tired because your powers kept you from sleeping._ Maybe that wasn't the case. There was a lot going on at work, a lot going on with his friends, and he was still coping with the death of his brother. He had every reason to feel stressed and tense. Probably it was just the stress that was keeping him awake, and the sleep deprivation was making him paranoid. _Probably._

A few minutes later he had arrived at S.T.A.R. Labs. He pushed through the double glass doors, swiped his key card, and hit the button on the elevator. Impatient, he hit it again, but when he did, he felt a weird pulse of energy pulsing at his fingertips, and he heard the elevator jolt to a halt inside of the shaft. Irritated, he hit the button again, but it was useless. _Did I do that?_

He stumbled up the stairs and into the lab. Barry and Caitlin were already there, talking about something over the computers. They glanced up when they heard him walk in.

"Hey Cisco," Barry greeted him, waving a hand. Caitlin's face lit up when she saw him.

"Hey Cisco," she said brightly. "It's good to see you. We thought maybe you weren't coming in."

Cisco stared at her, confused. "What are you talking about? I'm not that-" He looked up at the clock on the wall. It was 10:30. "-late."

 _10:30? I left the house at 7. It only takes me thirty minutes to get to work._

 _What was I doing for three hours?_

He realized that Barry and Caitlin were staring at him, looking puzzled and a little bit worried. He forced a fake smile onto his face.

"I, uh, slept in, I guess," he lied. "Sorry I'm late." He joined them at the desk and collapsed into a desk chair, trying to make it look casual but he was worried they had caught on to his exhaustion. "So, what do we got?"

 _I don't know where I am. It's not the highway. This is new._

 _"Francisco." I know that voice. It's deeply familiar, and yet I can barely recognize it._

 _"Who said that?" I glance around, but I can't see anyone. I am alone._

 _"Hello?" I look down at my hands. They're vibrating again. I can see a small field of energy forming at my fingertips._

"Who said what?"

Cisco's head snapped up again. He blinked, trying desperately to reorient himself. "Huh?"

"Earth to Cisco." A hand waved in front of his face and he realized Barry was sitting next to him. "Hey. Who were you talking to?"

"Um…" Cisco blinked again and forced himself to sit upright. "No-one."

Barry gave him a weird look. "You said 'who said that'."

"I just… zoned out for a minute." Barry didn't look convinced. "I dunno, man, what's it to you?" He said angrily, and stood up to get away from Barry, who looked hurt. Cisco didn't give a damn.

"Dude, were you Vibing? Because if you were-"

"Yes- I mean, _no,"_ Cisco corrected himself emphatically. "I wasn't. I didn't see anything." He didn't want to talk to Barry about any of this. Someone, but not him. Barry had lost that privilege himself.

Infuriatingly, Barry just looked more concerned. "Are you feeling okay? No offense, but you look terrible."

"I'm fine." Cisco angrily slammed down the files he had been holding. He hadn't known he was holding them. Where did they come from? What was he doing? Thoughts raced through his head and overwhelmed him.

 _"Francisco."_ It was the same voice again, but this time it was louder. Cisco snapped his head up, trying to discern where it came from.

"Who are you?" he said out loud, his eyes darting around frantically. He tripped around the corner of the desk, accidently knocking a mug onto the floor. It shattered at his feet, but he didn't even glance at it.

"Cisco-" Barry's voice sounded far away.

 _"You don't need your friends. You're more powerful than you know."_

"Where are you?" Cisco shouted, and his migraine seized his head again. "Show yourself!"

" _Cisco!"_ He felt Barry's hands grab his shoulders. He tried to look at Barry, but his face seemed blurry and out of focus. "Cisco, you're scaring me. Who are you talking to?"

Cisco stared at Barry numbly. "I- I dunno." He felt his legs weaken as he slumped to the floor.


	2. Chapter 2

_As soon as I become aware of my surroundings, I feel a sense of dread wash over me. It's dark again. I appear to be alone, but I know I'm being watched._

 _"Where are you?" I look around, but it doesn't even feel like I'm moving. It's like I'm stuck in limbo._

 _"Cisco." It's that voice again._

 _I laugh nervously. "So, uh, you got the name memo, did you? I appreciate it, because, uh, the only person who calls me Francisco is my mother. And that brings back all sorts of traumatic-"_

 _"Cisco." This time, the word comes out as an unsettling laugh, and the voice is so familiar that it pains me that I can't place it exactly. "You're embarrassing yourself. Do you even realize how much you're capable of?"_

 _"Uh, yeah. The Vibe thing is pretty sweet. I can use the Vibes to help my friends, and it actually helped me pick up a chick once."_

 _"Is that all?" The voice feels louder now, closer. "Are you really content being Barry Allen's sidekick? Don't you ever want to use your powers to become something more?"_

 _"No!" I cover my ears with my hands like a little kid ignoring his parents. "No. Leave me alone. Get out of my head!"_

* * *

This time the migraine set in before he even opened his eyes. He groaned softly and rolled over onto his side.

"Cisco?" That was Caitlin's voice. She sounded so worried. He forced himself to open his eyes to see her.

He was in the medical bay, draped over a cot. Caitlin was leaning over him.

"Hey," she said, a forced smile on her face.

"Hey," he murmured, barely able to keep his eyes open from the pain and fatigue. "How long was I out for?"

"Not even an hour." Caitlin brushed his hair out of his face. "How do you feel?"

"Like a train ran me over," he muttered, and Caitlin laughed softly.

"Listen, you need to start taking better care of yourself," she said firmly. "You're severely dehydrated and you're clearly exhausted. Have you been having trouble sleeping?"

"A little bit." Cisco forced himself to sit up, even though it made his head throb.

Caitlin frowned at him. "How much is a little bit?"

"I dunno, a couple of days ago it was four hours… last night was more like three. Some nights I can't sleep at all." He rubbed his eyes, exhausted, and then realized that his hands were shaking again. He quickly stuffed them into his sweatshirt pocket so Caitlin wouldn't see. She was watching him suspiciously.

"Barry said you were talking to yourself," she said carefully. "Like you were hearing voices?"

"Barry." Cisco scoffed on the name. "Where is he anyway?"

Caitlin sighed. "He's upstairs, working, because I suggested that due to your- animosity -towards him, it might be better for him to give you some space right now."

"The only animosity I have is with his freaking double-standard about time travel," Cisco grumbled.

"You're evading the question."

She had him. "Okay, yeah, I was hearing things. I think it was some Vibe related thing."

Caitlin leaned forward quickly. "You're having Vibes again? What about?"

"Uh…" He combed a hand through his hair awkwardly. He didn't want to tell her that he'd been dreaming about his dead brother- she didn't want her to know how much pain he was still in over Dante. But he also didn't want to tell her about the mysterious voices -that would make him look just plain crazy. "I've been having these vibes- I thought they were dreams at first -about Dante. When he died."

Caitlin was very quiet for a moment. "I'm sorry. That sounds rough."

"Yeah." Cisco stared straight ahead at the wall.

"Barry said you were talking to someone," Caitlin pressed. _Damn it._ Sometimes she was too sharp for her own good. "Was that part of the vibe?"

"I- I dunno. I think I just kind of drifted off." He shrugged, trying to look innocent, but this only made her look more worried. She opened her mouth to say something but he cut her off. "Cait, it's fine. I'm just tired and overworked. That's probably why all the Vibe stuff is going haywire. It's not a big deal.".

"Somehow I have a hard time believing that. Even by our standards, hearing voices isn't a good sign." Caitlin looked at him for long while with an expression somewhere between sympathy and frustration. "There's no chance I could convince you to go home and rest, is there?"

"I don't think I can." Cisco clenched his shaking hands into fists.

Caitlin sighed. "Okay. Just let me take your vitals and then I'll let you go. We'll figure this out, Cisco."

The rest of the day was slow and unremarkable. No news on Alchemy, no metas causing trouble. All Cisco wanted was a distraction, but the rest of the world wasn't obliging. He caught himself blacking out multiple times, but he didn't think anyone noticed.

* * *

Around 5 o'clock, it became obvious that nothing notable was going to happen that day. "I think I'm gonna clock out, guys," Barry announced, sliding his arms into his jacket. "Got a hot date with a hot reporter."

"Don't get too comfortable," Caitlin advised. "It seems like whenever you're with Iris, we have some crazy metahuman emergency."

Barry laughed at that, grabbed his backpack and made for the door. He stopped and glanced back at Cisco, who was playing idly with a desk ornament, a Star Labs snow globe. He didn't even know why they had it.

"Hey, Iris said she has a cute friend at work who's new in town. Maybe we should double up sometime."

"And be overshadowed by dream boy Allen?" Cisco muttered, turning the snow globe over in his hands. "No thanks."

Barry's smile vanished. "Dude, I'm trying here. Give me something." Cisco didn't look up. Barry sighed, said goodbye to Caitlin, and left.

A few moments of silence passed, and then Caitlin said, "You can't resent Barry forever."

"Watch me." He turned the snow globe upside down and watched all the tiny pieces of glitter float to the top.

Caitlin gave a frustrated huff. "Cisco, the work we do here depends on us trusting each other, and the things we do are too important to be jeopardized by you resenting him."

He dropped the snow globe on the desk with a loud clunk. "Me resenting him? So I'm the one who has a problem." He kicked off of the ground so that the chair he was in swiveled around to face Caitlin. "It's not like this is a petty disagreement. This is a legitimate moral discrepancy. He's willing to jeopardize the entire timeline and everybody else's lives, but only when it benefits him. Going back 15 years to rescue his mom and alter the outcome of a major catalytic event is no problem, but we can't go back a couple weeks and save Cisco's brother from a drunk driver."

"Cisco, that's-"

"What? Unfair? Untrue? Because I'm pretty sure it's neither of those." He crossed his arms.

Caitlin bit her lip, clearly uncomfortable. "All I'm saying is that it's really important that you are able to trust Barry."

"Well, maybe we shouldn't trust him."

"Cisco!"

"I'm just saying." He shrugged. "If I can't trust him, I think the issue is more with him than with me."

"Can't. You mean won't."

"Why are you defending him?" Cisco demanded, his voice breaking with anger. "He screwed up our lives. Out of pure selfishness. He killed my brother, and you expect me to meet him halfway?"

"Cisco!" Her voice came out as a frustrated shriek. She paused, composing herself. "Barry did not kill Dante."

"He was responsible!" Cisco spat, a hard edge to his voice. "Not only that, he refused to save him when him saving _his_ dead family member was what got Dante killed in the first place!"

Caitlin covered her face with her hands and inhaled deeply. She looked back up at him, obviously taking great pains to keep her voice level. "I'm sorry Dante died, and I'm sorry you're hurting so much. But do not accuse Barry of things that didn't happen just because you're looking for somewhere to place the blame."

Cisco felt his body start to tremble again, involuntarily. He sunk his head into his hands, too exhausted to keep fighting with her.

More silence. He couldn't stop shaking. Then Caitlin: "Are you crying?"

His head snapped up. "No, I just... it's these damn Vibe powers." He raised his right hand so she could see the trembling. She rushed forward to get a closer look and examined his hand, perplexed. "At first I thought it was sleep deprivation, or I was having a nervous breakdown, but..."

"It's energy," Caitlin murmured. "It's like when you used your powers that one time on Black Canary, except-"

"Except I can't turn it off." He looked up at her, his face vulnerable, admitting defeat.

Caitlin turned his hand over in her own. "When did this start happening?"

"About a week ago. About the same time as-" He stopped himself just in time. He didn't want to bring up his hearing voices again- he had just barely gotten out of that one earlier.

It was too late. She had caught on. "The same time as what?"

Cisco tore his hands through his hair anxiously. He didn't like lying to her.

"The same time as when my vibes about Dante started," he said firmly, and she nodded, convinced.

"Well, the good news is now that we know this is a Vibe thing, we can fix it," she said. "I'll take a look at the data we collected last year when you got your powers. There's got to be something helpful in there."

"Do you want me to stay and help, or-" He trailed off.

"You should go home and rest." Caitlin was already at a file cabinet, looking for the data in question. She glanced over at him. "If you think you can."

"Yeah." Another lie. "I can try, anyway."

"Good. That's what's important right now." She dropped a heavy stack of files down on the desk and looked back up at him. "I have a lot of work to do. Be safe." She leaned forward and gave him a quick hug.

* * *

He stared at the test tube he had taken home from work, trying to concentrate. Caitlin had made him realize something- the shaking wasn't his powers turning on him, it was excess energy. _Maybe if I can channel it, it'll stop._

He took a deep breath and held his hand over the tube. He tried to remember what it had felt like when he used his powers on the Black Canary, on the Rival, on Killer Fr- _on Caitlin._ He tried to envision all of the weird, shaky energy in his body concentrating at his fingertips.

He braced himself, and then…

Nothing.

"Dammit," he cursed aloud, and stood up, frustrated. Why wasn't it working? He did his best to focus on it-

Without warning, the test tube shattered and tiny shards of glass flew everywhere. Cisco froze, in shock.

 _Did I do that?_

He remembered the elevator at work. He had stopped it from working. He had done that without even thinking about it.

He tried again with another test tube. This time, he could feel his fingertips vibrating. He held his hand over it-

It shattered even faster this time.

Then a thought occurred to him. The vibrations worked on static objects because they had a very low vibration. But on Earth 2, Reverb was able to manipulate the vibrations of living things. Like people.  
 _Could I do that?_

Without another thought, he grabbed his jacket off the hook by his door and ran downstairs and outside. He looked around to make sure no-one was watching and then bent down over the black beetle that was lying on the ground. He started thinking about vibrational frequencies, and about disrupting them- and he didn't realize that he wasn't even holding his hand out when the beetle _shattered._

Cisco felt an unsettling feeling come over him, like his skin was crawling. If he could do that that easily, what could he do to people?

* * *

It was 4:17 AM. He hadn't slept even for a second.

Despite his best efforts to channel his power, he was still shaking uncontrollably. It had almost gotten worse since he had used them. He wanted desperately to call Caitlin- not just because she was the doctor who always had an answer, but because he was just plain scared and needed her comfort. But something inside of him convinced him to not reach out to her.

He hadn't Vibed since last night- or that morning? He couldn't remember which. But he could still hear the voice- not quite out loud, but more in the back of his head. When he had Vibed after passing out at work, he had recognized the voice, but hadn't quite been able to pin it down. It was driving him nuts, but he had an idea to pin it down.

He stood up and staggered over to the bathroom. He stared at himself in the mirror, trying to focus.

"Cisco." He said his own name out loud, cringing at how weak and shaky his voice sounded. He tried again, trying to dig into his diaphragm to make his voice sound deeper and more even. "Cisco."

Nothing. It wasn't working. He was just standing in front of the mirror at 4 in the morning chanting his name like a lunatic.

He had to try harder. He closed his eyes, trying to remember the voice he'd heard in his Vibes. _Like Captain Cold had a baby with an elocution textbook. Round the vowels, hang onto the consonants too long._ Without warning, he felt all of the pent-up energy in his body gather at his fingertips- just like it had earlier when he'd broken the test tube and the elevator button. _And the beetle._ He stared at his hands warily.

"Cisco," he tried again, and this time he felt the energy fly out of his fingertips, more like the times he had used it in combat before. The force startled him and he fell backwards.

The vibrating was extremely loud now- as if it was coming from an external source. He felt a slow sense of dread fill him as he staggered to his feet.

 _"Cisco."_ He nearly jumped out of his skin when he realized that his reflection had changed.

He was staring Reverb in the face.

 _Holy crap._


	3. Chapter 3

Swallowing was very difficult when his mouth was this dry.

His brain raced through the possibilities. Either he was hallucinating, or this was somehow Reverb from the past, or Reverb existed in another world…

Or this was a Vibe.

"What do you want?" he demanded, his eyes fixed on his alter ego.

"Francisco." Reverb's lips formed an unsettling smile. "I thought I'd never get through to you."

"Don't get too excited." Cisco stared him down, on guard.

Reverb laughed. It was chilling.

"Look. You don't really have a choice about what you're going to become. You might as well accept it. Trust me, that's the easy way out."

Cisco tried to look away, but no matter how he tried to avert his gaze, Reverb was still directly in front of him. His eyes were so dark and empty. "I'm not going to become you," he said loudly. "Just because you let your power corrupt you doesn't mean I have to. I'm going to use them to help people, like Barry-"

"Like Barry?" Reverb shook his head. "Listen to yourself, niñito. You know you don't want to be Barry Allen- the bleeding-heart hero who sees good in everyone. You don't need that." Reverb smiled again, unpleasantly. "You've seen what I can do. Aren't you curious to see what _you're_ capable of?" Cisco was silent. He couldn't deny that the scientist part of his brain was dying to know exactly what he could do.

Reverb smirked. "That's what I thought. But you've tried, haven't you? You've- experimented?" More silence. More smirking. "Y'know, there's a reason why you've never gotten far. Why every time you think you're getting somewhere, you hit a dead end."

"Stop… talking." Cisco shook his head, as if it would somehow get Reverb out of his mind. Reverb knew exactly what to say to get under his skin.

"The thing is, you can't be Barry Allen. It's impossible. The Flash's powers are impressive, sure. _Flashy."_ Reverb grinned at his own pun. "But they're incredibly limited. He has some cool party tricks, and he may have saved the world on a few occasions, but the range of _how much_ he can do is affected by the limitations of his- albeit strong -human body. All you have to do is exploit the natural vibrations of the world. You could be a god."

"I don't want that either." He tore his hands through his hair, anxiously. "I don't _need_ that. Every single day I go to work and I help keep the universe safe. That's enough power for me."

"Really?" Reverb's voice sounded flat, bored. "You have a whole world of possibilities open to you, and you choose nine-to-fives with the white hats. You do realize-" he paused, a single hand raised in a dramatic gesture. "-you could save Dante."

His breath caught in his chest for a moment and his mind began to race. "Don't you dare say his name. I'm not going to let you manipulate me."

Reverb laughed again. "Oh, I don't have to."

"What does that mean?" Cisco demanded, and he felt his hands start to shake. _Oh, dammit, not now._

"You feel that?" Reverb's voice felt like acid on his shattered nerves. "That's what I'm talking about. It's not a matter of if you start using your powers, it's when. See, your body can't handle all that pent-up energy. As soon as you put that energy to use, it'll go away." Cisco stared at his trembling hands, trying to force himself to stop moving. "And just imagine- if this is how your powers make you feel, imagine what you'd be capable of if you used it instead of letting it use you."

"Just get out of my head!" Cisco's head snapped up, and all at once, he felt a surge of energy race through his body and out of his fingertips. A wave of energy burst from his hands and shattered the mirror and Reverb with it.

Before his mind could even begin to process what had happened, he realized that something was wrong. _I just blew up a mirror two feet away from my face. The shards went everywhere._

 _But I'm not bleeding._

* * *

He was on the bathroom floor again. His mind felt numb.

 _Get up. See if you were right._

He reached up and grabbed the doorknob to pull himself up- and he was staring into the eyes of his own reflection. The mirror was completely intact.

 _Did I Vibe that whole thing? Reverb, and-_

 _No, it wasn't a Vibe. That never happened in any universe, and it couldn't happen in the future, because Reverb is dead. Which means-_

 _It was a delusion. Which means that Reverb wasn't saying those things to me._

 _I was._

He felt himself trembling again, involuntarily. He was shaking and tired and numb all at once and he was scared of himself. What time was it anyway? Maybe he could go to work. He checked his phone: 5:15 AM. _Dammit._ He couldn't be alone with his thoughts right now but it was way too early to go to work.

He should call Caitlin. She wouldn't mind him waking her up, especially with what had happened yesterday. But if he did, she would want to know why he was awake and why he was so scared- and he hated lying to her but he couldn't tell her the truth. He sure as hell wasn't going to call Barry. Even if he wanted to tell Barry what was happening, Barry would overreact to the whole thing. _He'd probably lock me up in the pipeline._

He needed someone who he could trust, but also someone who had the very specific range of knowledge to help him- and someone who wouldn't react emotionally and unpredictably.

He needed Harry.

 _Finally something you can do with your powers._ He knew how to open breaches, he'd done it before. Never mind that he had only done it a couple of times, and that the last time he'd attempted to travel through dimensions with his powers he'd almost died. This was just a simple breach from one world to another. Just a temporal breach.

He closed his eyes and held his hand out in front of him, trying to focus. He tried to remember everything from when he'd visited Earth-2. He visualized S.T.A.R. Labs- not incredibly different from theirs on Earth-1, but generally shinier and more advanced. As he visualized his memories, he could feel the energy vibrating at his fingertips, and he could see the tiniest tear in the atmosphere in front of him. _Good. It's working._ He pictured Harry and Jesse and the last time he'd said goodbye to them. Jesse had just begun to harness her speed powers and she was racing all over the place like an excited teenage kitten.

The breach was getting bigger now- where his familiar apartment once was, he could see the purplish-blue light of space and time bleeding through. He closed his eyes, concentrating. The last time he'd said goodbye to Harry, Harry was typically stoic, but their last goodbye felt genuine. Harry had left just when it felt like they were really becoming friends. Was that the real reason he was going to see Harry instead of just calling Caitli-

Suddenly he felt as if his whole body was being jerked upwards, and he was somewhere dark. He suddenly gasped for breath, feeling as though his lungs had been ripped from his chest. What followed felt like the worst anxiety attack he'd ever had combined with 100 needles full of Vertigo. He felt his body being jerked around, but he couldn't do anything to control it. He was somewhere dark and colorful at the same time, and he wasn't moving but at the same time he felt terrifyingly untethered. He watched colors race past his eyes, but they were never directly in front of him. It was like what you saw in the back of your head when you closed your eyes, except it was all around him and racing past at a dizzying rate. Everything was spinning around him, but he also couldn't feel his own body moving. He could hear voices, but he couldn't make any of them out. It sounded like Harry's voice, but then it was Jesse, and then Barry, and then Dante, and then it was Caitlin-

 _Focus. Focus, dammit. Focus on her._

"Caitlin?" he didn't know how he'd managed to speak in this hellish out-of-body state, but he heard his own voice echoing somewhere. Maybe it was just a part of the cacophony of noise he was hearing- but he clung to it.

"Caitlin?" He heard her voice again- he still couldn't make it out, but it was just strong enough to rise above the rest of the pandemonium. "Cait? Where are you?"

"I'm here, Cisco." He could understand the words she was saying, but she still sounded so far away.

"Where?" He tried to look around, but he still felt weirdly disconnected from his own body. "I can't find you."

"I'm right here." Her voice was a little bit closer. "I'm right here, just- just follow my voice."

"I don't know how. I don't even know where I am." He felt a throbbing pressure where his heart should be- but he didn't even know where his body was anymore. Or if he had one. Was this like when Barry had been absorbed by the Speedforce? Had he somehow ripped his own being apart with his powers?

"I'm right here," she said again. "Just listen to the sound of my voice. Stay with me, Cisco."

"Cait," he said again, his voice hoarse. He could feel his voice vibrating in his throat. That was progress. _Focus on the vibrations. You can control them._ He tried to remember what his heartbeat felt like- suddenly it was hard to remember. He focused on that throbbing pressure and tried to imagine a heart pumping blood. He tried to remember the usual rhythms of his pulse- when he was excited, when he was working out, when he was trying to fall asleep. Then he tried to picture his lungs- expanding as they filled with air, and then depressing as he breathed out an exhale. He felt the crushing pressure soften into a numb throbbing, and the burning lack of oxygen turned into a dull breathlessness. _Control the vibrations._ He started counting the beats of his heart. _1, 2, 3, 4, 5, 6, 7, 8-_ it was going too damn fast. _Slow down. Breathe._ He inhaled and could feel air filling his chest. He could feel the comfortingly normal vibrations of his body slowing returning.

"His vitals are all over the place." It was Caitlin, but she was talking to someone else. That must mean he was getting closer. _Get it together._ The vibrations of his body felt more synchronized now, so he tried something different. He visualized all the vibrations- of his heartbeat, of his lungs, of his pulse -and directed them towards his hands. He tried to envision a field of energy at his fingertips, how he'd sent out pulses of energy before. _Come on. You can do this._

Suddenly, the blur of color in front of him came into focus and became more monochromatic. It was blue now- purplish blue.

"Come on, Cisco. Stay with us." Caitlin's voice was so close- right through the patch of purplish-blue. _The breach._ He focused on the energy in his hands and in an instant, he was ripped from his surroundings again.


	4. Chapter 4

In an instant, he was ripped upwards again and his lungs were consumed by the same painful burning sensation. It wasn't just like he'd had the wind knocked out of him, it was as if the oxygen had been sucked out of the air. He blacked out as he felt his body thrown against something solid. It was a wall. He was out of that weird- whatever it was. Vortex?

He groaned weakly. His eyes felt heavy and when he opened them, the scarce light made them burn. He felt weak and he was shaking again. _Dammit._

Cisco opened his eyes and stared around for a moment, trying to place his surroundings. It was dark and he was in an apartment- there was a large window to his left and a door on the other side of the room.

He felt a sharp pain in his face and realized his nose was bleeding. _Crap. The last time this happened was when Barry caused a temporal rupture… except I didn't. So what is happening to me?_

* * *

Caitlin was jolted out of a deep sleep when she heard a loud thump from outside her bedroom door. It wasn't just a thump- it had been accompanied by a somewhat electronic whir. _It's got to be a meta. Although we don't have any on the loose right now, and if we didn't know of them they wouldn't have a reason to come after me. What kind of meta could make that noise?_

She sat upright and quietly jumped out of bed. She looked around frantically for anything that could be used as a weapon. She settled on the small lamp that sat atop her dresser- she could turn it upside down and yield the hard metal base as an effective blunt object. She cracked the door open and winced when it creaked _. I really should keep a real weapon in my room. Based off of the number of break-ins we've had in the lab, I'm actually shocked I've never had a meta break into my apartment before._

Caitlin squinted to look through the tiny crack in the door, bracing herself for the worst. All she could see was a shadowy figure standing in the corner. She opened the door and raised the lamp, preparing to defend herself, when the figure in the corner spoke out.

"…Cait?"

Caitlin froze, lowering the lamp. "Cisco?" she asked, bewildered.

He stood up and practically tripped forward into the light, confirming that it was him. Her heart sank when she realized how sick and weak he still looked. He looked up at her and offered an exhausted, mirthless smile.

It took her a moment to process the situation, but when her brain caught up, she exploded. "What in the hell are you doing? Showing up, unannounced in the middle of the night? I mean, of course you're always welcome here but you scared the wits out of me!"

"I'm sorry," he mumbled, and looked down. His weak, tired voice should have elicited her sympathy, but instead it made her even more exasperated.

"It's not just me! You can barely stand! You should be sleeping, not traipsing across town in the middle of the night! You should've called if you needed something, you know I would have come to you!"

"I didn't," he muttered.

"You didn't what?" Caitlin asked indignantly.

"I didn't- I didn't come," he murmured, and that was when Caitlin realized he looked even worse than the last time she'd seen him. His eyes were bloodshot and had a faraway look in them, like he couldn't see what was right in front of him. His forehead beaded with sweat, his nose was bleeding, and he was holding onto the wall as if he could barely stand.

"What do you mean?" she asked carefully, taking a few steps forward. He stepped forward to meet her in the middle of the room, but his legs buckled beneath him. Caitlin was at his side in an instant. She wrapped her arm around his back and helped him over to the couch. As soon as she took her arm off of him, he collapsed onto the sofa. His whole body seemed to go limp, but his eyes were still open, just staring straight ahead.

She waited a few moments to see if he would speak. When he didn't so much as look at her, she realized that something was seriously wrong. She shoved her worries aside and switched gears to doctor.

"Cisco, I'm going to ask you some questions and it's really important that you answer them. Even if you can't remember, just try your best, okay?" He nodded blankly. "What's the last thing you remember before you got here?"

"I was in my apartment," he mumbled.

"I need you to be more specific than that." Caitlin leaned forward and pressed her fingers against his neck to take his pulse. She glanced at the clock on the wall to keep track. "Do you remember where you were in your apartment?"

"Uh…" He paused, still staring straight ahead. "In my room… I think."

"Why were you awake?" It had been a minute. _145? That's too damn fast, he'll have a stroke if I don't get his heartrate down._ She pressed the back of her hand against his forehead. _Too damn hot. He's probably dehydrated._

"I didn't sleep all night, Cait. Haven't in days." Hearing him speak a full sentence made her realize how slurred his speech was. "I was freaking out- I was scared."

Finally, they were getting somewhere. "What were you scared of? Did you vibe Dante again?"

Cisco shook his head. "What did you Vibe about?" Again, he shook his head no.

"I was hallucinating," he mumbled. "He- he was talking to me."

Of course he was. "Dante?" she asked, to get him to keep talking.

"N- yes." Even in this pathetic, delirious state, he still caught himself. Caitlin saw right through his lie.

"Cisco, tell me the truth. Who was it?"

"It was Dante," Cisco insisted, and for the first time in five minutes, his eyes changed expression. From vacant to terrified and defeated. "What's wrong with me?"

"You're sick." She reached forward and brushed his hair behind his ear, an almost subconscious reaction. "I don't know why yet, but I'm gonna figure how to help you."

"I don't think you can." Cisco laughed, but it was a hollow and bitter sound.

"I definitely can't if you won't talk to me," Caitlin said firmly. "So please tell me the truth. What's the last thing you remember doing?"

"I- I opened a breach." He tore a hand through his thick black hair, his expression tense. "I was trying to go to Earth-2, to-"

"-to see Harry," Caitlin finished, and sighed. Of course Cisco's instinct would be to go to Harry, his mentor and a genius, because she hadn't been able to help him.

Cisco nodded, surprised. "Yeah. But it didn't work. I- got stuck inside the breach. I was stuck inside this, like, vortex thing. Straight outta Star Trek. And then I heard you talking and I ended up here."

"You heard me talking?" Caitlin leaned forward. "What was I saying?"

"I- I dunno." He shook his head, distressed. "None of it made any sense. I must have been hallucinating again." He sunk his head into his hands miserably. "I think I'm losing my mind."

"Maybe you're not hallucinating," Caitlin suggested. "Maybe there's another explanation. Like when Barry first got his powers, he thought something was wrong with him, because his body wasn't used to such a fast metabolism, faster sensory comprehension- until he found out what happened, he probably thought he was losing it too." His head was still dropped down to his knees but she could tell that he was listening. "There could be some element of your powers that we haven't discovered yet, something that's affecting you because you don't know how to utilize it. Maybe - if this is how your powers make you feel, imagine what you'd be capable of if you used them instead of- being used."

Cisco slowly lifted his head up to look at her. "What did you say?" He asked, looking at her apprehensively.

"I mean, just look." She picked up one of his hands, which was still trembling. "Your body is just full of pent-up energy. Maybe once you put it to use, it'll go away." Caitlin stopped talking when she noticed that Cisco was looking at her suspiciously. "What?"

He suddenly rose to his feet and backed away from her. "Dammit, I can't believe I fell for it again!"

"What are you talking about?" Caitlin stood up quickly, but he backed away from her, tearing his hands through his hair anxiously.

"Is anything real?" he mumbled, and started to pace feverishly. "Get out of my head, you jackass!" he shouted at the ceiling.

"Cisco!" Caitlin rushed to his side and grabbed his arm. "Shh, it's okay. It's just me." He was staring straight past her with such a horrified expression that even though she knew they were alone, Caitlin quickly looked over her shoulder just to make sure. No-one was there. She turned her attention back to Cisco and gently turned his head so that he was looking directly at her. "Listen, I don't know who else is talking to you right now, but I promise, it's not real."

He looked at her wordlessly, and everything on his face read fear and exhaustion.

"Come on," she said quietly. "Whether it's your powers or not, there's something messing with your mind and I need you to trust me to figure it out. Come lay down on the couch. I'll get you some medicine to help you feel better until we know what's causing this. I'll tell Barry to send word over to Earth-2 and with Harry over here we'll figure it out in no time."

He hesitated, and then sighed. "Yeah, okay." He wandered back to the couch and collapsed. Caitlin bit her lip with worry and then shook her head. She had to keep a level head. Cisco needed her.

* * *

Cisco stared at the ceiling tensely. Caitlin had given him something to slow his heart rate, but it was just making him feel more restless. Caitlin had stayed up with him for a while, but now she was fast asleep, curled up in the armchair on the other side of the room. He wanted desperately to tell her the whole truth, about how he'd seen Reverb, but it seemed like the wisest plan of action would be to keep it to himself until he knew _why_ it was happening.

He was pretty sure now that Caitlin was real and not a hallucination, but he was still wary. What she had said about him using his powers was almost exactly what Reverb had said verbatim. Of course, Reverb hadn't said that, that was his own thoughts using Reverb as a vessel to present them. So for all he knew, Caitlin was a figment of his imagination, too.

There were a lot of things he didn't know right now, and it frustrated the hell out of him. Why did his mind choose Reverb as a vessel for his thoughts? Why had he gotten stuck in that vortex when he'd opened breaches successfully before? His guess was that he'd gotten distracted by thinking about Caitlin while he was trying to open the breach, hence his ending up in her apartment- but why had he heard her talking while he was in the vortex?

He glanced over at Caitlin to make sure she was still sleeping, and then sat up. "Reverb?" he asked hesitantly. "Are you-"

"I'm always here, Cisco." Even though he had been expecting it this time, he still jumped when he heard the unnerving voice right behind him. "I'm an extension of your thoughts. Always with you."

"Right." Cisco winced. This was going to take some getting used to. He turned around to face Reverb. "So does that mean you can't tell me anything I don't already know?"

"Not exactly. I'm a manifestation of your subconscious. I can help you dig out things that you know, but wouldn't realize without my help."

"So this is like a Twin Peaks kinda deal? You're the Giant and I'm Cooper?" Cisco paused thoughtfully. "Or is it more like the Amber hallucination in House?" He shook his head. Not important. "Okay, but if you're just me, then why are you telling me things I don't want to hear? Shouldn't you just agree with me by default?"

"Like I said, subconscious. I'm all of the thoughts that you keep below the surface. I'm kind of like your dark side." Reverb grinned unpleasantly. "So yeah, I'm gonna say some things that you don't want to hear, but hey, you're the one who thought them."

Cisco paused, considering the implications of this. "But that means you can help me out, yeah? Since they're all of my subconscious thoughts- you can help me figure out things that I couldn't on my own. Like the-"

"-like the Amber hallucination in House," Reverb finished. "Yes. I can help you solve all the problems that have stumped you before. I can help you figure out how to use your powers, why you couldn't go through the breach, everything that you don't know the answer to. All you have to do is accept my presence and everything that comes with it."

Cisco bit his lip nervously. He was basically making a pact with Satan here. But what were his other options? Losing his mind and getting locked up by Barry? Besides, this was just an extension of his mind. How bad could it be?

He turned his attention back to Reverb. "Deal."

Reverb grinned. "I thought you'd say that."

Cisco glanced over at Caitlin. Still sound asleep. "Okay," he said, turning back to Reverb. "We have a lot of work to do."


	5. Chapter 5

As soon as they were out of the apartment building, Cisco turned to Reverb. "Start talking."

"Or you'll do what?" Reverb smiled a thin, disconcerting smile. "I'm in your head, bro. You couldn't get rid of me if you tried." Cisco rolled his eyes and started walking down the sidewalk.

Reverb reappeared in front of him and he winced, startled. "Is that really necessary?" he asked weakly.

"Yes." Reverb grinned. "Where do you think you're going?"

"Subway," Cisco answered. "Don't have my car." He took a step forward again.

Reverb shook his head. "You have so much to learn, hijito. You got here through a breach, so you can get back through one."

"Except _I_ can't," Cisco reminded him. "I tried going to Earth-2 and I got sucked into some Interstellar junk. Really don't want a repeat of that."

"You've opened breaches before," Reverb reminded him. "You can do it again. Think logically. What went wrong?"

"I- I got distracted," Cisco ventured. "I was thinking about Caitlin. That's why I ended up in her apartment instead."

"It's not just because you thought about something else. Our powers aren't that temperamental. Well, maybe yours are." Reverb smirked. "Instead of focusing on your destination, you were focusing on the people. You got sentimental. That's gotta go."

Cisco scoffed. "That can't possibly make a difference."

"I'm serious." Reverb's tone grew serious. "You got distracted because you were focusing on people. Your ties to humanity distract you from your full potential."

"Is this the part where you tell me that I have to shut myself off from my friends and become all callous and evil-villainy like you? Cause that's not happening." Cisco turned away.

"Letting go of your human emotions will make everything easier," Reverb's voice called out from behind him. Cisco turned back around. "Why do you think most metas turn evil? It's hard to reach your full potential with your conscience holding you back."

Cisco tore a hand through his hair. He already felt uneasy, and Reverb wasn't helping his conscience. But he couldn't go on like this- he needed to learn how to harness his powers. Not only that, he was desperately curious to discover his full potential- something he'd never managed on his own. And Barry had been begging him to come fight with him for months. Maybe his mind manifesting itself as his evil doppelganger didn't mean that he was going to become him. Maybe he could use his powers for good. He held out a hand to open the breach, and then hesitated. _Or maybe that's just what he wants me to think._

"Open the breach," Reverb urged him. "Focus on the vibrations and nothing else."

Cisco closed his eyes, letting himself feel the wind pass by him, the way it vibrated over every hair on his body, the faint trembling of the ground from the subway passing underneath. Once again, he felt the shaking in his body subside as the energy flowed to his fingertips. He felt a surge of energy, and then felt it release from his hands. He opened his eyes to see a large, purplish-blue mass in front of him.

"Beautiful," Reverb murmured approvingly. "Now enter. Stay focused."

Cisco took a step forward. Think about where you're going. He felt the energy of the dimension envelop him as he stepped through. The breach closed itself behind him, and then he realized- he was in the vortex again. Except this time, there was no vertigo or no eerie distorted voices. He was standing upright and fully in control.

"I see you've discovered one of our many powers." Reverb reappeared in front of him.

"Where am I?" Cisco looked around, overwhelmed.

"You're inside the breach. Instead of going directly from one location to another, you're in between. From here, the possibilities- both spatial and temporal -are endless."

"How have I never discovered this before?" Cisco asked, awed.

"You've never had a reason to open an inter-spatial breach before," Reverb reminded him. "You've always gone between worlds, not within your own. This gives you a different perspective."

"Wait." Cisco held out a hand, trying to process this. "What did you say about temporal and spatial possibilities?"

"You can go anywhere or to any point in time."

"Could I have done that on accident?" He asked, remembering the two and a half hours he'd lost a few days ago.

Reverb shrugged. "You're like an uncoordinated puppy when it comes to your powers, so yeah."

"Thanks for that." Cisco looked around, observing his environment. It was eerily still and quiet. "So I can really go anywhere?"

"Anywhere." Reverb smiled. "The choice is yours."

He could go anywhere. He could go to Earth-2, for real this time- _but you don't need Harry,_ his voice told him. _You have Reverb. You can figure this out yourself._

He closed his eyes, visualizing S.T.A.R. Labs- his S.T.A.R. Labs, not Harry's. He tried to feel the vibration of the air in the lab, of the fluorescent lights, of the computers. He saw the blue and purple fabric of the vortex dissipate, creating a small window through which he could see his workshop. He stepped through and into the lab.

"See?" Reverb smiled smugly. "It's easier when you separate yourself from your emotions."

"That's not why." Cisco shook his head. "It's because I was concentrating. My mind was all over the place before. I wasn't focusing."

"You can believe that if you like." Reverb shrugged. "You'll figure it out soon enough."

"Okay, are you actually going to help me or not?" Cisco snapped. "You helped me open a breach, big whoop, I've done that before. All you've done so far is be creepy and cryptic as hell."

Reverb smirked. "This isn't an instant thing, you know. Harnessing your full potential will take time."

Cisco was about to shoot back a retort when he remembered that he wasn't talking to Reverb. This was his mind personifying his subconscious thoughts in a way that made sense to his brain.

There was nothing wrong with this. This was all his brain. He was in control.

"Okay." He walked over to Caitlin's desk, where he found the stack of files she'd been studying the other day- all of the data they'd collected on his powers. The files were marked up with bright orange highlighter and riddled with post-it notes. He felt a twinge of guilt- she must have spent her whole night trying to figure out how to help him. And then he'd woken her up by falling out of a breach into her living room at four in the morning.

He glanced at the wall clock to check the time: 6:30. He had an hour and a half until the others showed up. He looked back at Reverb, who was watching him expectantly.

"I know how to travel between dimensions," he began slowly. "But I'm not very good at it. I can open breaches no problem, but if I go between dimensions myself, things get a little nosebleed-migraine-seizure-y. Can you help me fix that?"

Reverb grinned. "I thought you'd never ask."

"Okay, but-" He glanced at the door. He didn't want to risk someone coming in early and catching him. "Let's go to the basement."

Once they were in the basement, Cisco remembered something. "Wait, I need my Vibe glasses." He started back towards the stairs, but Reverb held a hand out.

"Nuh-uh. Those are a crutch. You don't need them."

"You used glasses," Cisco protested, and then remembered he was talking to himself. "Reverb did, I mean. This is weird."

"Well, they do look cool," Reverb admitted. "But you don't _need_ them. Now remember, traveling to other dimensions isn't your problem. It's only when you stay there too long that the deadly nosebleeds happen. That happens because your body is constantly experiencing different vibrational frequencies, and it causes even more stress when you go through your own breach to another dimension, because you're splitting your energy between two actions. And it's exacerbated by staying there longer, because since each Earth has its own vibrational frequency, your body can't recalibrate to the vibration that it's used to. So you'll have to teach your body how to recalibrate its vibrational frequency by giving it a little practice." Reverb crossed in front of him. "Instead of opening a breach to another dimension, you're going to Vibe into it. When you get Vibes, even though you're physically here, part of you is in a different location- wherever the Vibe is. So think about where you want to go, but instead of opening a breach, just Vibe."

 _Just Vibe._ That was easier said than done, but somehow, he already know how to do it. He closed his eyes, imagining how it felt to be on Earth-2. The air was ever-so-slightly different there- which was because each Earth had a different vibrational frequency -and he could feel it every time he went there. It was like his heart rate was out of sync with the rest of the world. He felt his body oscillating- like when he couldn't stop shaking, except this time, he was controlling it- and then it stopped.

Cisco kept his eyes closed for a moment, basking in the stillness. He felt the familiar foreign sensation of not-quite-right wind creeping over his skin. He opened his eyes to confirm- _I did it. I'm on Earth-2._

Except he wasn't quite there. As Reverb had instructed, he hadn't really gone there- he Vibed himself there. Which was probably the only reason his nose wasn't gushing blood at the moment.

"So?" He asked aloud, expecting Reverb to comment on his performance- but he was greeted with silence. He glanced around in confusion. Reverb was nowhere to be seen.

 _Where exactly am I?_ He looked around, attempting to place his surroundings. He was in a vast, empty warehouse- he didn't recognize it from any Earth, although there wasn't much about it to recognize. There was a smattering of gigantic wooden crates, some abandoned shelves, and it smelled vaguely sweet. He stepped forward to explore his surroundings-

At once he felt as if he'd been smacked in the head with a metal chair, and he was back in S.T.A.R. Labs.

"What the hell was that?" he shouted. "I thought you said that wouldn't happen if I just went in a Vibe!"

"You'll notice you're still conscious," Reverb drawled. "So I'd say you're doing better than usual. And I never said that you'd be fine regardless- I said there would be no repercussions from the simple action of getting there. That pleasant little headache was user error. You went too far, literally. Vibes aren't meant to be long-distance transportation- you're limited to a few square feet from where you arrive. Any further than that, you get booted. That's why you need to work on your travelling through breaches- but for now, it's better than nothing. It'll help your body adjust."

"Let's do that again," Cisco demanded. "I need to learn- I need to know how to be in control."

"Your wish is my command. Or is my command your wish?" Reverb paused, musing. Cisco ignored him and closed his eyes, trying to focus again on Earth-2. This time it was easier, because he had just felt the unfamiliar vibrations of Earth-2 across his skin. He tried to imagine his lungs filling with the foreign air, his heartbeat syncing with-

"Cisco?" He was ripped from his trance by Caitlin's voice calling from behind him. His eyes flew open and he spun around, his heart pounding.

Caitlin looked as exhausted as had felt all week. She had clearly just been sleeping- her hair was a teased mess and her eyes looked heavy, but they were wide open with worry. She rushed to his side and grabbed his shoulders.

"Hey," she murmured. "Are you okay?"

"Wh- yeah, I'm fine," he answered, confused, and then remembered what a mess he'd been the last time she'd seen him. "Better than before, anyway."

"Good. That means I won't feel bad about this." She pulled her hand back and slapped him across the face. He recoiled, stung in every meaning of the word. When he lifted his head back up, her face alight with anger.

"What the hell is wrong with you, Cisco? You stumble into my apartment in the middle of the night _obviously_ not stable in any meaning of the word and I stay up with you _all_ night and then you just take off?"

"I'm sorry," he mumbled lamely, but she wasn't done.

"Look, I know you're not in the best place right now, and I know you hate feeling helpless, I know you like to take matters into your own hands, but you need to give me more credit than this! Can't you just _trust_ me to help you for once?"

"I trust you," he tried to say. She shook her head.

"Clearly, you don't, or you'd have woken me up instead of taking off! When I realized you were gone, I was terrified, because goodness knows what you might do with your powers going haywire and in this mental state. For all I knew you could've been-"

"Could've been what, Cait?" He interrupted her, surprised by how cold and biting his words sounded. "Misusing my powers, committing some heinous crime? Like Reverb?"

"I-" She stopped and frowned. "Who said anything about Reverb?"

"I dunno, you implied it." He bit his lip. "Y'know, I already feel like I'm losing control. I don't need you to help me doubt my sanity. I've got that covered."

"I didn't mean-" She softened. "I'm sorry. You just scared me." She put a hand on his arm and he twisted away.

"Scared you why?" he demanded. "What do you think I would do that scares you so much, huh? It's just me, Caitlin." His voice broke and he ducked his head so that she wouldn't see the pain on his face. "You keep asking me to trust you, but do you even trust me?"

"I'm sorry," she said softly, and he felt her hand on his arm. Her cold touch against his burning skin was jolting, but it felt good. _Her hands are so cold…_

He looked up to meet her eyes. She looked guilty and heartbroken. These last few days must have been hard on her. He opened his mouth to apologize, but something behind Caitlin caught his eye-

Reverb. He shook his head, his mouth open in the shape of a foreboding _no._

 _Your ties to humanity distract you from your full potential._

He looked back down at Caitlin. Her eyes were sad, but the corners of her mouth were lifted in a hopeful, tentative smile.

"You just think that I'm going to turn into Reverb because you're afraid of turning into Killer Frost," he said coolly, and Caitlin's face fell.

"What?" she asked, and quickly pulled back her hand that had been holding his back to her chest. "Why would you say that?"

He shrugged. "We don't know what's going on with my powers, but you're assuming that it's something that needs to be fixed. You're assuming that just because you don't want your powers that I don't want mine either."

"I never said anything like that," she protested. "Cisco, listen to me, you're not-"

"What? Thinking straight?"

"Yes." This time she didn't reach out to comfort him. She folded her arms, establishing distance between them. "I never said your powers were a bad thing, but obviously whatever it is that's been going on for the last few days can't be good."

Cisco paused for a moment, realizing how hurt Caitlin looked and sounded. He contemplated apologizing, but his eyes met Reverb's again. Again, Reverb slowly shook his head.

"Maybe you're wrong," he said flatly, and Caitlin stiffened. She opened her mouth to shoot back a response, but they were interrupted by a reddish streak of lightning bursting into the room, and Barry was instantly in front of them.

"Hey," he said, breathlessly. "Sorry, Caitlin, I just got your texts." He looked from Cisco's stony expression to Caitlin's distraught one and his face fell. "Are you guys- okay?"

"I'm fine," Cisco spat, turning away from them, and then realized that for the first time in days, that statement was true. He didn't feel weak or shaky anymore. He felt awake and present, and stronger. He turned for the stairs.

"Where are you going?" Caitlin's voice could have frozen lava.

"I'm going upstairs," he replied without turning around, keeping his voice dangerously level. "I don't know about you two, but I have work to do." He retreated quickly up the stairs before Barry could say anything.

He came up the last flight of stairs and heard the sound of two hands slowly applauding him. Reverb was sitting in his chair behind the computer desk, a sinister smile on his face.

"Well done," he said approvingly. "Who knew you had it in you?"

"You made me do that," Cisco said suddenly. His voice shook. "That wasn't me."

"Oh, but it was," Reverb said coolly. "That was you, just getting a little bit closer to your full potential. I told you I'd help you, didn't I?"


	6. Chapter 6

Cisco slammed the door to his workshop and collapsed into his chair. The way he had treated Caitlin freaked him out, because it _was_ him- he _had_ been angry at her, he _had_ wanted to push her away, but he knew it was wrong. But it had completely come from him.

Reverb was getting to him. Right now, he was standing on the other side of Cisco's workbench, leering at him. _There's got to be some way I can block him out._

He grabbed his headphones off of his workbench and plugged it into his phone and chose the first song he saw- _Master of Puppets_ by Metallica -and turned it up to top volume. He put his headphones on and leaned back in the chair and closed his eyes.

 _End of passion play, crumbling away…_

"Cisco." It was Reverb's voice. Even over the earsplitting electric guitars, Reverb's voice was still as clear as day. Cisco tried to ignore him.

 _…I'm your source of self-destruction…_

"You can ignore me all you want, but you can't avoid what you're going to become."

 _…leading on your death's construction…_

"The sooner you come to terms with who you really are, the happier we'll both be."

 _…obey your master, your life burns faster…_

"I gotta hand it to you, your capacity for denial is impressive. I didn't think you'd last this long. You seemed pretty weak to me."

"Just shut up, okay?" Cisco shouted, keeping his eyes closed. "You're not real."

Listening to Metallica at a deafening volume wasn't cutting it. He needed to focus on something else. He reached for the first thing he saw on his workbench- a blueprint he'd drawn for an inter-dimensional extrapolator. Okay, where had he gotten stuck with this last?

He found his prototype, buried under a mess of papers on his bench, dusted it off and got to work. He managed to distract himself briefly- for a few minutes, he was so immersed in his work that he completely forgot about Reverb. Then he made the mistake of looking up-

"Thought you could forget about me, eh?"

"Just-" He covered his face with his hands. He had to find a way to get Reverb out of his head. He had already learned how to better control his powers- the shaking had stopped hours ago -and Barry and Caitlin could help him figure out the rest. Having Reverb in his head wasn't doing him any favors. It was just making him hostile and unpredictable, and he didn't need that. He stood up and walked quickly to the door.

"You're making a mistake." Reverb reappeared on the other side of the door. "You need me. You won't be able to control yourself without me."

"This is me taking control." Cisco turned away and started walking quickly towards Caitlin's lab. "You're a delusion. You're not real."

"Do you really believe that?" Reverb's voice was hard and serious.

" _Yes."_ He paused and turned to face Reverb. One last time. "You said it yourself. You're an extension of my thoughts. You're just my mind personifying my insecurity about turning into you- into Reverb." He turned back around, his hand on the doorknob.

"Or maybe I'm your mind trying to tell you something," Reverb called after him. "Trying to shut off your mind's signals is a huge mistake."

"Listening to you was the mistake." Cisco opened the door and slammed it behind him.

"Cisco?" Caitlin was sitting behind her desk, but stood up quickly when she saw him. "What do you want?" Her voice was cool and reserved.

"I-" He got distracted when Reverb reappeared behind Caitlin. _It's just a delusion._ He forced himself to look Caitlin in the eye. "I need an anti-psychotic."

Her expression immediately switched from steely anger to concern. She rushed forward to him. "Are you okay? What's going on?"

"He's in my head." Reverb was standing right next to Caitlin now.

"Who is?" Caitlin grabbed his shoulder and looked into his eyes.

"Don't tell her," Reverb said aloud. "This is the biggest mistake you could make."

"Stop talking!" Cisco stumbled backwards and turned to face Reverb. "Just- just stop!"

"Cisco?" Caitlin was at his side, and looked in the direction that he was looking, obviously trying to understand what he was seeing. "Who's in your head? Are they talking to you?"

"Don't listen to her," Reverb warned. "She won't help you."

"Whoever they are, don't listen to them," Caitlin said quietly. "It's not real. I'm the only one in here, I promise."

"When has Caitlin ever had your best interest in mind?" Reverb reminded him. "She always has an agenda. She and Barry are just trying to drag you down to their level. But you could be so much more."

He forced himself to look back at Caitlin, who was visibly tense. "Anti-psychotic, Cait. Now."

"Yeah." She stood up and ran over to the door that connected the lab with the speed lab. "Barry!" she called. "I need you."

Cisco slumped against the wall and sunk his head into his hands. He realized his headphones were still hanging around his neck, blaring Metallica so loudly that he could hear it even without the headphones on.

 _Master of puppets, I'm pulling your strings…_

"Cisco, listen to me." It was Reverb. "I know this isn't what you want to be, but by trying to force it off, you're just going to hurt yourself."

 _…blinded by me, you can't see a thing…_

"Caitlin and Barry don't understand you. You don't need them. You're capable of so much. Maybe you just need to prove it to them- or to yourself."

"What do you mean?" he asked quietly so that Caitlin couldn't hear.

"Use your powers. Kill the Flash."

"Caitlin!" he shouted, and brought his head to his knees.

"Think about it. Barry is the one who's kept you from using your powers in the field. Barry is the one who is always locking up other metahumans. And he's the one with the good guy complex. Without him, imagine what you and Caitlin could be. You could help her reach her full potential."

"Hey, Cisco." Barry's voice was right in his ear and he felt a hand on his back. "Hey, hey, talk to me."

"Don't let him in," Reverb warned. "Caitlin is one thing, she's your friend, but Barry? He's selfish. He doesn't care about you. If he knew what you could become, how powerful you could be- he'd lock you up in a heartbeat. Come on, just give him a little seismic blast. You don't have to kill him, just break his ribs or something. He heals quickly. Just show him who's the boss."

" _No!"_ Cisco snapped his head up and before he could stop himself, he felt energy burst from his hands and towards where Reverb was. Of course, he missed, and instead an office chair erupted into pieces.

"Cisco!" Barry stared at him, shocked, but Cisco hardly noticed. He was dead focused on Reverb.

"You need to stop," he said, hating how his voice shook.

"What are you talking about?" he heard Barry say.

"I told you, you just need to accept who you are." Reverb shrugged.

"This _isn't_ who I am!" Cisco raised his hands and sent another seismic blast towards Reverb, this time shattering a shelf of test tubes. Reverb smirked.

"You said it yourself. I'm not here."

Cisco raised his hands again, but then there was a sharp burst of red lightning and he was on the ground. It took him a second to realize that there was something on his wrists- he looked down and realized he was wearing his own power-dampening cuffs. He looked up to see Barry looking down at him, a grim expression on his face.

 _He'd lock you up in a heartbeat._

"Barry, what are you doing?" he demanded. Before Barry could answer, Caitlin rushed over with a glass of water and two small orange pills in her palm.

"These are for you," she murmured, kneeling down next to Cisco. "They should help with the hallucinations."

He pushed her away. "I'm not taking those until _he_ explains why he just cuffed me with my own tech." He jabbed a finger at Barry, and then stood up. He eyed the pills in Caitlin's hand suspiciously. Maybe that was a sedative and not an anti-psychotic. Maybe they were trying to trap him.

Caitlin looked at Barry expectantly. He shrugged and sighed. "I'm sorry, Cisco, I panicked. I thought maybe you weren't… in control." To Cisco's surprise, he reached forward and removed the cuffs.

"To be fair, I'm not sure I am, either," Cisco admitted. He took the pills from Caitlin and then the glass of water. The water felt so good on his dry lips- Caitlin was right, he was dehydrated. Had he been forgetting to drink? Probably. The last few days had been such a blur, especially for the last 12 or so hours when he'd had Reverb in his head.

The three of them were silent for a moment, and then Caitlin spoke. "Who were you talking to?"

Cisco opened his mouth to say "Dante" and then realized that lying to them wouldn't do him any good. "Reverb. He's been appearing on and off for- for a couple of days now."

"You told me you were seeing Dante!" Caitlin exclaimed, and folded her arms reproachfully. "You lied to me."

"I'm sorry, I was scared." Cisco looked at the ground. "I thought you would think I was crazy."

Barry and Caitlin exchanged looks. "What was he saying to you?" Barry ventured.

"I dunno." Cisco ran a hand through his hair anxiously. "I think- I think I might be turning into him."

"You're not turning into Reverb," Caitlin assured him. "Just like I didn't turn into Killer Frost. Turning evil is a choice, and you can choose not to."

"Maybe." The anti-psychotic hadn't fully taken effect yet, but Reverb was starting to fade. Barry offered Cisco a hand and he accepted it, staggering to his feet.

"We can talk about this while you lie down." Caitlin put her arm around him and they walked him to the Cortex. Barry leaned against the wall and Caitlin stood beside him.

"Alright, Cisco, I'm going to ask you some questions and I need you to be honest." Caitlin raised an eyebrow at him. "Like, really this time."

He nodded. He was too tired to object.

"Okay." She took a deep breath. "When did you start… hearing Reverb?"

"Like two days ago. The first time I passed out at work." He scratched his head awkwardly, hating that he'd been such a mess lately.

"Have you been dreaming about Dante still?" she asked.

He shook his head. "They weren't dreams, they were Vibes. And… now that I think about it, I haven't Vibed about him since… since I started hallucinating Reverb."

"So maybe you weren't hallucinating," Barry suggested, and they both looked at him. He shrugged. "It makes sense, doesn't it? Maybe it was a Vibe somehow."

"Maybe," Cisco said doubtfully, but he didn't want to tell them the truth, how Reverb was an extension of his subconscious thoughts. That would just make him sound crazier.

"Have you used your powers at all the last few days?" Caitlin asked him. "Besides just now, I mean."

"Yeah, a few times. Just to travel between locations and… I kinda went to Earth-2." He played with his hands nervously. "Pretty standard stuff."

"Just the other day, you were shaking uncontrollably." Caitlin picked up one of his hands, observing it. "That seems to have gotten better, at least."

"Yeah," Cisco agreed. "I think… it seems like it got better when I used my powers."

"That makes sense," Caitlin agreed. "Because if it was pent-up energy, it makes sense that using your powers would release it."

"So if what's been happening to Cisco is because he doesn't use his powers, that's not a big deal," Barry reasoned. "You can start training with me. It would be cool to have you fighting with me."

"I don't know," Caitlin murmured. "Not about that, I mean, I think there's more to this than lack of use. It's been causing tachycardia, psychosis-"

"The tachycardia can be explained by the crap ton of vibrational energy," Cisco pointed out. "And Reverb is gone. So I think that got better too."

Caitlin shook her head. "That would be the quetiapine kicking in. I want to run some more tests."

"Caitlin, running tests only gets you so far," Barry pointed out. "You can run all the tests you want, but it doesn't change the fact that we have no idea what we're dealing with. Maybe we just need to do something. Let me train with him."

Caitlin pursed her lips. "Maybe." She looked back at Cisco. "I want you to try to get some sleep first."

He laughed mirthlessly. "I can't fall asleep in my bed at night, Cait. I doubt I'll be able to sleep at work in the middle of the morning."

"Then I'll give you something to make you sleep," she said firmly. "You need sleep, Cisco. I'm not comfortable with you messing around with your powers until you can walk in a straight line. You need to catch up on sleep and you need IV fluids; you're still dehydrated."

He looked at Barry and shrugged. "Fine. But I can't sleep all morning. It's still crazy early. Is it even seven yet?"

Barry looked at Caitlin quickly, and then back at Cisco. "Dude, it's almost eleven."

"What?" Cisco felt an unpleasant pit in his chest. "What do you mean? I got here at 6:30 and you two… you got here a few minutes later."

Caitlin shook her head. "Barry had to go to the police station and I slept in. We didn't get here until 10:15."

"It can't be eleven." Cisco shook his head and looked around for a clock. It was 10:50.

"And you'll have some empirical evidence in a second when H.R. gets here," Barry added. "You know he would never be here before seven."

Just as Barry was speaking, they heard footsteps out in the lab. "Where is everyone?" the familiar voice of Harrison Wells called out.

"We're in here," Caitlin called, and H.R. appeared in the doorway, wearing his signature dumb fedora.

"What are you all doing in here?" he asked, and then spotted Cisco. "You look terrible," he commented casually, and sipped a coffee in his hand.

"Can he leave?" Cisco muttered to Caitlin, and Barry ran to the door and escorted H.R. away. Caitlin closed the door and turned back to Cisco.

"You could try being nicer to him," she chided.

"I can't." Cisco leaned back against the wall. "He walks around with Harry's face on, but he isn't a tenth of the person Harry is."

"It's not his fault who he looks like." Caitlin was sorting through bottles of pills and produced a small white pill. "Here. This should help you sleep."

"Thanks." He swallowed the pill with water and leaned forward, his head in his hands and his elbows resting on his knees. "Seriously, why do we even keep that guy around? He's not even a scientist. He never does anything-"

"Cisco." She shoved his shoulder gently. "You're never gonna fall asleep sitting upright and complaining about your coworker. Lie down." She stood up and went back to the counter, where she was preparing an IV.

He obliged and rolled over onto his side so that he was still facing her. "I really thought It was seven."

Caitlin turned her head so that she was facing the wall completely. "I know," she said quietly.

"That happened the other day, too. Me losing time, I mean."

"I remember." She turned back to face him. "Don't worry. There's got to be an explanation for all of this. Who knows, maybe it's not even to do with your powers. Maybe it's a neurological condition and it's just making them act up." She rolled the IV rig over to the bed and sat down beside him.

"Maybe." They sat in silence for a minute, then he pushed himself up into a sitting position with one arm. "Cait?"

She had gotten distracted fiddling with the IV needle. "Yeah?"

"Can you bring me my cuffs? The power-dampening ones?"

She looked surprised. "Why do you want them?"

"I dunno, it's just-" he hesitated. "When Reverb's in my head… I'm not always in control. I don't want to hurt you."

Her expression softened. "Of course. I'll go get them." She stood up and went back to the lab and left the door open behind her. A couple seconds later, H.R. poked his head around the door frame.

"Wow, Francisco, you're being possessed by your evil doppelganger? Now _that_ is some Stephen King stuff right there. I gotta write that down for my book."

"H.R.!" Barry appeared next to him, looking apologetic. "Cisco is really tired, so we should probably-"

"Possessed?" Cisco sat up straight, indignant. "What exactly did you tell him, Barry?"

"Well, he didn't say possessed," H.R. admitted. "But it's creepier that way, don't you think?"

"This is more than creepy enough for me," Cisco said firmly, and then remembered something. "What were you doing in my lab the other day? You don't even know anything about science. Why is it that every version of Harrison Wells in the multiverse likes to invade my space?"

Caitlin reappeared at the doorway, cuffs in her hands. "What are you two doing in here?" She asked pointedly, and glared at Barry.

"We were just leaving," Barry said quickly, and shoved H.R. through the door.

"Why are you bringing him the metahuman cuffs?" H.R. questioned. "Ooh, is this a power struggle? That's _definitely_ gotta go in my-"

Caitlin pushed the door shut. "Do you see why I don't like him?" Cisco asked dryly.

She ignored that. "You shouldn't be sitting up." She walked over to the cot and slid the cuffs onto his wrists. "There you go." She turned her attention back to the IV. "Give me your arm." He obliged, and she held the needle just above the surface of his skin. "Take a deep breath." She slid it into his arm and he winced slightly. She noticed his discomfort with a mixture of amusement and indignance. "Hey, if you don't like it, maybe be an adult and drink water next time." She secured the needle with a white piece of medical tape.

"Thanks." He leaned forward. "Sorry about the last few days. I promise not to have another mental breakdown for a while."

"It happens." Her mouth formed a thin, worried smile. She gently pushed him again. "Lie _down._ I want you to get some sleep. H.R. is right, you do look terrible."

"He's right about something for once," Cisco snorted, and Caitlin shoved him again, but harder. "Hey," he protested, but slid down onto his back. She walked over to the door and flipped off the light.

"I'll stay here until you fall asleep, in case Reverb decides to show up." She sat down on the stool next to his cot. Her face was mostly in shadow, but there was a line of light from the crack in the door that split her face down the middle. "You're going to be okay, Cisco."

"Thanks, Caitlin," he murmured, and felt his eyelids growing heavy.

* * *

 _I'm on the side of the highway again._

 _August 9th, 2016, 8:30 PM._

 _Again._

 _"Feels real this time, doesn't it?" A familiar voice says in my ear, and I know I am not alone._

 _"Go away, Reverb." I try to focus on Dante's car and the blue Jeep going too fast behind him. Somehow reliving this tragedy I've watched a dozen times is more comforting than listening to the unnerving voice next to me._

 _"If you insist." I can practically hear the smirk in his voice. "Is this better?"_

 _I turn to face him to see what he means- and I stagger backwards a few steps._

 _He's not Reverb anymore. The man bun is gone, the pretentious guyliner is gone, and so is the sweet-ass black leather jacket._

 _His hair is down, he's not wearing makeup and he's wearing an open button down over a t-shirt._

 _He's me._

 _"What are you doing?" I gasp, but he just smiles smugly and steps forward into the road. He waves frantically at Dante's car, and Dante slows down._

 _He opens the passenger side door and I can hear him frantically shouting at Dante, but I can't make out the words. The blue Jeep is fast on their trail. In a crazy maneuver, he pushes the driver's side door open and he and Dante both tumble out of the other side. The Jeep smashes into the car, but Dante is safe._

 _"Cisco, you saved my life," I hear him say, and Reverb reappears beside me._

 _"You can save Dante," he says in a dramatic whisper. "It'd be as easy as going to Earth-2. Save Dante."_

 _"No," I murmur, and cover my eyes, trying to block him out. "I can't. It would rupture the timeline. Ruin everything."_

 _"Barry ruined everything to save his mother. No-one stopped him. Including you."_

 _I try to protest, but suddenly I'm not talking to Reverb- I'm in the passenger seat of Dante's car._

 _"Thanks for looking out for me, hermano," he says, and his dark brown eyes bore straight into mine. I try to look away, but they're entrancing. I haven't seen him in so long…_

 _"Yeah, no problem." My voice sounds hoarse and weak. "You'd do the same for me."_

 _"Of course I would." He claps my shoulder, and I can actually feel his hand on me. This is way too real. "We're brothers. That's what we do."_

 _"No, just stop it! It isn't real!" I shout, and in an instant, Dante is gone, and with him, the car and the highway. I'm back in a dark room, staring straight into Reverb's eyes, but he's still dressed like me._

 _"I'm trying to show you what you could do. You know you want to do it." He shrugs. "But I suppose if I can't persuade you by showing you what could be, I should show you what_ will _be."_

 _"What are you talking about?" I can feel all the blood rushing away from my face._

 _"Come on." He snaps his fingers and we're out in the middle of a street, but not the highway. A few yards away from us, I see Caitlin- but she doesn't look like Caitlin, she's wearing a tight-fitting jacket and there are streaks of white-blonde in her hair -and I'm there, too. Wearing my Vibe goggles._

 _She's hurling icicles at me and I'm shattering them with seismic waves. I think at first that this is the past, when Caitlin was losing control and I was defending myself. I quickly realize I am gravely mistaken._

 _"You don't have to do this," she calls out, and her voice is thick with tears. "Please come back to me. You don't have to become this, Cisco."_

 _Future me looks up at her with a cold grin. "The name is Reverb." He sends another huge wave at her, and this time, she is caught off-guard and crumples to the ground._

 _"Caitlin!" I shout, and rush to her side. The scene fades away and I am facing Reverb once again._

 _"You see?" he says quietly. "That's what you become. There's no avoiding it."_

"Cisco!"

* * *

He sat upright, feeling as if his heart would pound out of his chest. He felt Caitlin's hand on his shoulder, but her touch felt like acid to him.

"Listen to me, just breathe," she said, but her voice sounded far away. "Whatever you saw… it's gone now. Just breathe."

He dropped his head into his hands, trying to force himself to calm down. It was just a dream. Just his mind messing with him. None of that was real. _It can't be._

"Breathe." Caitlin was sitting next to him, rubbing soothing circles into his back with her fingers. "Breathe in for four seconds…. hold it for seven… breathe it out for eight."

He tried to follow her instructions, but his mind kept racing over what he'd just seen. Was it really the future? He remembered the Vibe he'd had from Caitlin a few weeks ago. He thought it had been fulfilled when he fought her the night she kidnapped Julian, but now he remembered that there was an important difference between the Vibe and what happened that night. In the Vibe, she'd been full Killer Frost, or looked it, anyway- her hair was blonde and she was wearing that sweet jacket. When they'd fought, she'd still more or less looked herself, except for the creepy glowing eyes.

In the scene Reverb had just shown him, she had looked exactly as she had in that Vibe.

When he Vibed that, he had assumed that she was the evil one and he was defending himself.

But what if… what if it was the other way around?

"I have to go," he muttered, and stumbled to his feet. He ripped the cuffs off of his wrists and threw them to the ground.

"What are you doing?" Caitlin grabbed his arm urgently. "Cisco, whatever you're about to do… please, think about it first…"

"I'm sorry." He ripped the IV needle out of his arm and let it drop to the ground. He held out his hand and this time, the breach opened instantly.

Barry appeared at the doorway. "Cisco-" he began, and raced forward, but he was too late. Cisco stepped forward into the breach and it closed up behind him.


	7. Chapter 7

Cisco paused for a moment, looking around the Vortex. Where did he want to go? He considered going to Earth-2, but at this point, what could Harry do for him? He needed answers, and not the kind you could get from running tests and analyzing data. He needed to know for sure if he became Reverb.

Since he couldn't Vibe himself, he needed to be a little bit more creative. What had Reverb said- from this vortex he could travel to anywhere in time or space. Was time travel really that easy for him? It seemed preposterous. The only way Barry could time travel was by running insanely fast, and even that had its limitations. But he had Vibed to the past in his sleep countless times, so there had to be a way for him to Vibe to the future. He closed his eyes, envisioning the fight he'd seen between him and Caitlin. They'd been on a road somewhere... when he'd seen it before, he'd gotten the impression that it was in the future, but not the distant future. He felt the air around him shift and he opened his eyes.

Just a few yards away from him, he could see Caitlin, her hair streaked with white and her skin even paler than usual. There was freezing mist gathering at her hands as she raised them towards... Cisco? Reverb? It was definitely him, wearing his goggles, but whether he was Reverb or not he couldn't tell. He took a few steps closer so he could watch.

"Killer Frost," Future Cisco said in a cool, even voice.

"Cisco," she answered, her voice dangerously level. "You don't have to do this."

"Cisco isn't home." He advanced forward several steps. "I'm Reverb now."

"Cisco, please," Caitlin begged, and the tiniest icicle began to form in her palm. "I don't want to hurt you."

"I don't want to hurt you either." He grinned unpleasantly. "I want you to join me."

That was enough. Cisco closed his eyes quickly and he was back in the Vortex. So that was his future. He became Reverb and fought Caitlin. Okay. But when was it?

He closed his eyes, focusing on where he'd just been- or, rather, when. This time, instead of going to that street, he imagined Central City Picture News, hoping that he would travel back to the same time.

He felt the air change and he opened his eyes. He was standing in front of the newspaper headquarters. What day is it? He wandered over to the newspaper stand to check the date on the paper- May 20th, 2017.

Six months from present day.

In six months, he was full Reverb?

His head spun and he closed his eyes, back in the vortex again. He opened them and he was in front of Central City Picture News again, but he was back in his time. He could feel it just from the air.

What time was it? He stepped forward so that he could see the face of the clocktower: it was 4:30. The last time he'd seen a clock, it had been 11:00- but who knew if he'd slept through most of that time, or accidentally time-traveled, or lost time again.

He was all too aware of the stares he was attracting, and he realized how he must look. He was still in sweats, his face was pale and his eyes shadowed. He needed to get out of here and get back home, so that he could have some space to process what he'd just learned. If someone provoked him enough, he might lose control- but for some reason, he wasn't as concerned about that as he should be. He needed to go home and regroup-

"Cisco?" He looked up and realized Iris was standing right next to him.

"Oh, hey, Iris." He combed his hair behind his ear, trying to look casual.

She smiled. "What are you-" Her gaze trailed down to his arm and her eyes widened. "Oh my gosh, you're bleeding." He looked down and realized his forearm was covered in blood, and there was a spot in the middle that was deeply bruised. It must have been from where he ripped the IV out.

Iris reached for his arm and he stumbled backward. She looked at him quizzically, taking in the rest of his disheveled appearance.

"Are you okay?" She asked doubtfully. "You don't look so good."

"Yeah, I'm good." He flashed her a smile, which probably just looked demented.

She appraised him again. "You're wearing a S.T.A.R. Labs sweatshirt, which means you were in the med bay for some reason," she pointed out. "And you're not wearing shoes." He looked down and realized she was right. She looked at him and narrowed her eyes. "You're not supposed to be down here, are you?"

"I-" he stammered. "What are you doing here?" He retorted lamely.

"I _work_ here," she said gently. She looked at his bleeding arm again and then reached for her phone. "I'm calling Barry."

"No!" He said sharply, and she looked at him, startled. He backtracked. "I mean... that's not necessary. I was just going home."

"What are you gonna do, walk a mile and a half to the subway barefoot?" She challenged. He didn't have an answer to that. She started to dial a number on her phone. "I'm gonna call Barry, and he'll-"

"No!" He grabbed her wrist, not realizing that his hands were vibrating with energy. When he secured his grasp on her, there was a surge of energy and he felt the vibrations leave his hand. There was an audible crack and Iris cried out in pain and recoiled.

Cisco stared at her, dumbfounded. "Did I-" he stammered. She grabbed her wrist and looked up, her face twisted with pain.

"I think you broke my wrist," she gasped.

He stared at her, panic rising in his throat. "I'm so sorry," he mumbled. "I didn't mean to do that."

She smiled, but it was forced. "It's okay, Cisco. I'd drive you home, but-" she gestured with her good hand to the one he'd broken. "I'll call Barry and he'll take you home, okay?"

He opened his mouth to respond and then froze, realizing the implications of what she'd just proposed. When Barry found out that he'd hurt Iris, he would freak out. He remembered how quickly Barry had turned on him earlier when he'd lost control for a brief moment, and now that he'd actually hurt someone- Barry's girlfriend no less -he'd probably lock Cisco in the Cortex.

"I gotta get out of here," he muttered.

"I don't think you should go anywhere like this," Iris said urgently, but Cisco wasn't listening. He held his hand out and opened a breach. Iris' eyes widened.

"Cisco, what are you doing?" She hissed. "In public? In plain si-"

He raced through the breach and it closed up behind him.

* * *

When Iris told them what happened, Barry lost it.

"We need to find him right now," he commanded, pacing back and forth in front of Caitlin, Joe, Iris and H.R. "Before he hurts anyone else."

"Barry, listen to yourself," Caitlin chided him. "This is Cisco we're talking about."

"He hurt Iris!" Barry exploded.

"It's not like he tried to kill me," Iris said, a frustrated edge in her voice. "I'm not made of glass. I think I'll survive a broken wrist."

"That's not the point." Barry pushed his hair back with his hand. "The point is that he broke our trust."

"It was obviously an accident," Iris shot back. "He was scared. I think Cisco needs our compassion right now, not our judgement."

"I would agree, but Bar has a point," Joe spoke up. "How do we know he's safe? When Caitlin went all Killer Frost on us, she couldn't control herself." Caitlin looked away. "It was like Caitlin wasn't even in there."

"I think this is different than that," Caitlin said softly. "The last few days he's been slowly losing control of his powers, but as far as I can tell he's still at the wheel."

"That doesn't make it better," Barry protested. "If he's aware of what he's doing, he should be able to stop himself."

"I don't think it works like that," Caitlin said. "It seems like... whenever he gets emotional or scared, he loses control. I just need to go calm him down."

"That's a great thought, Dr. Snow, but we have no idea of knowing where he is," H.R. pointed out.

"Yes we do." Caitlin kicked the ground and the chair she was in swiveled to face the computer. "You know how people from other earths vibrate at different frequencies than ours? So they created cellular deadspots wherever they went. Cisco's vibrational frequency constantly fluctuates when he uses his power, so he creates cellular disruptions. So..." she hit a few keys on the keyboard and waited a few seconds. "He's... at his apartment." She frowned, then shook her head and stood up. "I'm going to him."

"What if he tries to hurt you?" Barry asked.

"He won't," Caitlin said confidently. "And if he tries..." she looked down at the cuffs on her wrists. "I'm more than capable of defending myself," she said grimly.

Barry looked at the others, expecting them to back him up, but they were silent. He sighed. "Okay, fine, but I'm coming with you."

* * *

Cisco stared at his hands. They weren't shaking. So why had he lost control?

He held his hand over the glass plate in front of him and it shattered, and the energy instantly switched off. He had perfect control over his powers. So he shouldn't have lost control... had he wanted to hurt Iris?

He had expected the confirmation that he became Reverb to scare him, but somehow, it didn't. He felt exactly the same. It scared him more that it hadn't scared him.

"Cisco?" There was a knock at his door and he heard Caitlin's voice. "I know you're in there."

He stared ahead at the wall, willing her to go away. She didn't.

"Listen, I don't know what you're feeling right now, but... no-one blames you for hurting Iris."

He stood up and placed his hand on the doorknob, but he heard Reverb's voice flash through his head again.

 _Your ties to humanity distract you from your full potential._

He slumped to the ground and leaned his head against the door. He was too tired to fight back.

There was a long pause, and then Caitlin spoke again. "Whatever is happening to you isn't your fault. We can fix this together, just... you have to stop shutting me out."

"I become Reverb," he blurted out, and there was another heavy silence.

"What do you mean?" She finally asked.

"I... I Vibed to the future and... I'm him." He tore a hand through his hair.

Another pause. The silences were getting awkward now. "Cisco, can you please open the door?" She asked gently. More silence. "Please let me in. I can't help you if you keep me at a distance like this."

He reached up and turned the doorknob, cracking the door open so that he could see her face. He was so damn tired. "I don't want to be Reverb," he croaked.

"You don't have to be." She reached for his hand and he backed away. She looked at him, hurt.

"I'm... not always in control," he explained. "I don't want to hurt you. Like Iris-"

"Iris is fine," Caitlin said reassuringly. "You just lost control for a brief moment, but you're stronger than this."

"I'm not." He shook his head. _You seemed pretty weak to me,_ Reverb said in his head again. "How can I be, if I become-"

"Cisco." She grabbed his hand with both of hers. He tried to pull away, but she tightened her grasp. "Whatever you saw is not set in stone."

"But it's the future," he insisted.

"If we've learned anything, it's that the future is never concrete," Caitlin reminded him. "I believe that we write our own futures. If you believe that you're going to become Reverb, it becomes a self-fulfilling prophecy. But it doesn't have to be that way." She held her hands out. "Look at me. I thought I was doomed to become... her." She couldn't even bring herself to say the name. "But I didn't."

 _Because you hid from yourself and suppressed your powers,_ Cisco thought, but didn't say it out loud.

"You're better than this," she said quietly.

"I'm not sure I am," he mumbled.

"I know you are," she said earnestly, and grabbed his hands again. "You're better than him. You could never be him." She reached forward and brushed a wayward strand of hair behind his ear, looking into his heavily shadowed eyes. "You're exhausted, aren't you?" She murmured.

"Like you wouldn't believe," he mumbled.

"Do you need me to bring you sleep medication again?" She asked. "Or you can come back to the lab-"

"I'm good, Cait," he interrupted. "I think I can fall asleep here." That was a complete lie. Really, he just wanted to be alone. She knew better than to push him.

"Okay," she relented. "But promise that if you need anything you'll call me."

"I will." He started to close the door.

She grabbed his arm. "You promise?"

"I promise." He smiled, but it didn't quite meet his eyes.

She threw her arms around him and pulled his body to hers. "We'll figure this out. I promise."

"Yeah." He leaned his head against her, almost subconsciously, just leaning into her touch. He never wanted to let go of her, and yet he found himself pulling away. "I'm- I'm really tired."

"Okay." She started to leave, and then turned back around. "You promise-"

"I'll call." He pushed the door closed behind her.

* * *

He didn't remember falling asleep, but the next thing he knew, he was on his bed. He rolled over to check his alarm clock: 7:14 PM. It had been eight hours, so the quetiapine should be out of his system by now.

He sat up. "Reverb?" He called out. No response.

He stood up and looked around cautiously. He was alone.

Reverb was gone.

"Finally," he murmured, and then grabbed his head when the migraine kicked in.

He sunk to his knees and leaned forward, resting his head on the bed. Before he'd let Reverb in his head, his powers had been seriously messing with his body- the shaking, the migraines -but while he'd surrendered himself to Reverb, all the symptoms had gone away. And now they were back. Was it some kind of trade off? If he wanted to be free from Reverb, he had to deal with his powers ripping him apart?

A few minutes later, he managed to stagger to his feet. He stumbled to his bathroom, opened the medicine cabinet and reached for the aspirin bottle. He shook out the last pill and downed it with a lukewarm glass of water that was on his nightstand. He collapsed back on his bed and turned on his phone while he waited for the medicine to kick in.

A missed call and two texts from Caitlin. _How are you feeling?_ and _Get any sleep yet?_

He wrote back: _Crappy, and yeah, a little bit._

She buzzed back a second later: _Hallucinating still?_

 _Nah. I think he's gone._

He turned off his phone and set it down on the nightstand; the glare was just aggravating his headache. When it didn't go away, he got up to double his dose, and then remembered that that was the last aspirin. So he grabbed his jacket and wallet and headed out the door.

Once he was down the stairs and out of his apartment, the noises of the street- cars racing by and honking horns, people's feet hitting the ground, the dull grumble of the subway beneath- got into his head and overwhelmed his senses. He dug in his jacket pocket and pulled out his sound-canceling earbuds and popped them in.

That was better. The throbbing subsided and softened to a dull burn in the back of his head. He connected his earbuds to his phone and hit shuffle. He let the beats of the music sync with his footsteps and his heart rate and his slow, regular breathing. He started counting his footsteps in sets of three, pacing the downbeat of his footsteps with the pulsing of his heart. As he passed by the rest of the world, he couldn't hear its sound, but he could feel the vibrations. The wind vibrating over the surface of his skin, the impact of other people's feet hitting the ground, the way the pavement quaked under his feet when the subway passed through. Blocking out the house and just feeling the vibrations connected him to the world in a new way, and it was oddly comforting.

He felt an arrhythmic set of vibrations racing past him and he looked sharply to the side. A figure in a black hoodie was running up to a woman and knocked her to the ground. He took off across the street with her purse in tow. The woman opened her mouth, presumably crying out for help, but he wasn't concerned with sound.

He raced across the street after the assailant. He felt the cars rumbling across the street screech to a halt just in front of him. By the time he got to the other side of the street, there was a small crush of people exiting a nearby movie theater, and he lost track of his target. He closed his eyes, trying to pick out the feel of the uneven footsteps amongst all of the other vibrations he felt through his feet. He raced through the crowd, pushing past everyone in his path. He spotted the black hoodie a few feet ahead of him and raced forward. He grabbed the guy's arm when his back was turned and shoved him against a nearby wall.

"Hey asshole," he shouted, but he couldn't hear his own voice, just the vibration of his voice in his throat. "Give me that purse."

The guy turned to face him, revealing himself to be a dusty-haired, sallow-skinned teenager. He smirked.

"You and what army, short stuff?" He taunted. Cisco realized that one of his earbuds had fallen out.

He took two steps forward so that he and the kid were face to face. He grabbed his wrist, feeling vibrational energy gather at his fingertips.

"Give me the purse," he said in a low voice, and felt a tiny wave of energy release from his fingers and into the kid's arm. He whimpered with pain, but Cisco tightened his grip.

"You can't make me," the kid spat at him, and tried to twist away. Cisco let go of the kid's wrist and grabbed his hand, and released a burst of energy into the kid's little finger. There was a loud crack and the kid yelped.

"Okay, I'll give you the damn purse!" He shouted, and threw it at Cisco. He darted away and disappeared through the crowd.

Cisco turned around to see a distraught young woman standing behind him. "Is this yours?" He asked, holding it out to her.

Her face lit up. "I thought I would never see that again!" She reached forward and hugged him. "You're my hero."

"No problem," Cisco said awkwardly, and pushed away. He popped his earbud back in, successfully drowning out the sound of the rest of the world. He turned around and started walking back towards his apartment.

What had he done? He had practically tortured somebody. _It was a thief_ , his mind rationalized. But it was just a teenager.

As he walked idly back to his apartment, he realized his body was on fire with adrenaline. Had he enjoyed that?

He didn't realize until he was unlocking his front door that he had forgotten to buy aspirin. _Great. Maybe I can ask Caitlin to-_

He took out his earbuds and paused, realizing that his headache was completely gone.

Well, that was interesting.


	8. Chapter 8

Cisco stopped dead, hand on the doorknob. He hadn't even noticed that the migraine had stopped. He had chalked it up to dehydration and sleep deprivation, but it stopped all on its own. He couldn't claim Caitlin's level of medical expertise, but he was pretty certain that ear-splitting migraines weren't supposed to stop by themselves. _When did it stop? More importantly, why?_ Had it stopped when he put in the noise-canceling headphones? It could have been triggered by sensory overload- no, because even though the barrage of noise and sound on the city streets had exacerbated his headache, it had started when he was alone in his completely silent apartment. Maybe it was a hangover from the cocktail of sedatives and anti-psychotics that Caitlin had administered to him throughout the day- no, the only thing that might still be in his bloodstream was the quetiapine, and he wasn't sure, but he didn't think that anti-psychotic drugs were supposed to cause migraines.

He ran down a mental checklist. _Headache- gone._ He looked at his hands. _Not shaking._ He carefully surveyed the dark hallway, as if Reverb might be hiding in the shadows. _Hallucinations, also gone. I feel fine._

Cisco jerked the front door open and closed it behind him. He looked down and realized that his hands were pulsating with energy. His powers had just turned on without him even thinking about it. He tensed his hands into claws and closed them into fists, trying to turn the energy off. Barry was right, he needed training if he was ever going to be remotely helpful with his powers. But right now, helping the Flash was the last thing that he cared about. He could still feel his heart racing with adrenaline from apprehending the teenage delinquent, and damn, it felt good. For the first time in what felt like days, he didn't feel like he was out of control.

Except… he _was_ out of control. This was the second time that day that his powers turned on without him consciously thinking about it. He'd had his powers for almost a year now, and he hadn't ever experienced this lack of control until a few days ago, until… _Reverb._ He had let Reverb into his head, and now he couldn't control himself. But Reverb was gone, and so were the other symptoms he'd been experiencing. If he had been sick, he wasn't now.

He wandered into the kitchen and found his favorite mug- it was black and displayed the structural formula for ethanol underneath the words "Technically alcohol is a solution". He was about to turn on his coffee maker when he remembered it was 8:00 pm. On the other hand, he had taken a three-hour nap and his sleep schedule was already screwed up beyond repair. He was filling up the coffee maker when he remembered Caitlin's lecture about proper hydration. _And if I don't she'll stick more needles in me._

The water tasted like plastic, but focusing on something physical helped to slow his heart rate and descramble his mind. He rested his arms on the counter and slumped over it, staring at abstract patterns in the granite. They all looked like wavelengths to him. If he stared at them long enough, they seemed to move and ripple in earthquake patterns.

He felt his hands trembling again with pent-up energy that dared him to use it, to hurt another person. He remembered how that same energy had sent the Black Canary flying across a warehouse, how he'd used it to knock Caitlin to the ground when she was Killer Frost- but those times had been different; they were self-defense. When he'd broken that kid's hand, some sick part of him had enjoyed it. What was worse was that that realization didn't horrify him nearly as much as it should have. Besides, he'd barely even hurt that kid- _thief._ He was a thief, and also seemed like an asshole, and a broken finger would heal.

 _But Iris-_ Cisco felt the breath catch in his throat as he remembered what he'd done to Iris. _Is she going to be okay? Is it going to heal? What if I shattered her bones to dust?_ He felt his face heat up and his head throb again with that freaking migraine. _This isn't who I am. I don't hurt people._

He dropped the water bottle on the counter, stumbled into the living room and collapsed onto the couch. He pressed his hands to his temples and inhaled, trying to force his heartbeat to regulate itself. _You need to calm the hell down. Freaking out solves zero problems._ He closed his eyes and tried to focus on breathing deeply and slowly, but all he could think about was what he'd done to Iris- more painfully, how he'd _felt_ while he was doing it. Shocked, originally, because he hadn't meant to do it. Worried, because he knew Barry would freak. But nowhere in that mess of emotion was remorse. Iris, who was sometimes the only other sane person on Team Flash, who helped Cisco hold the team together when they were all on the verge of falling apart. Iris, who went to see The Force Awakens with him when Caitlin said it was overrated; Iris, who he'd _literally_ fought zombies with. He'd hurt her and _he didn't even feel bad about it._

A sharp _rap_ burst into his thoughts and he sprang onto his feet, feeling his pulse accelerate again. _When did I get so damn jumpy? It's just the door._ He shuffled over to the front door and cracked it open.

"Caitlin," he said, unsurprised to see her on the other side of the door.

"Hey," she said, and smiled. "Can I come in?"

"Uh, sure." He opened the door wider and held it for her. She walked in, heels clicking, and turned to face him. "I, uh, didn't get your text."

She raised an eyebrow. "My text?"

"To say you were coming over." He crossed his arms. "Y'know, common courtesy and all. I always give you a heads-up."

Caitlin rolled her eyes. "That is entirely untrue, but also beside the point. In any case, I think the last three days are more than enough to warrant me checking on you. As a doctor and as your friend." She strode forward and into his kitchen, appraising the bare counters. "Either doing dishes is some kind of therapeutic action for you or you haven't eaten recently." She looked up to him in a silent question.

Cisco scratched the back of his head awkwardly. "I mean, I dunno-" He couldn't remember eating recently, but he had lost a lot of time the last few days. Maybe his brain had been so overloaded what with Reverb and his powers going haywire that it had blocked out the more menial details of the day to save energy. He looked up to answer Caitlin, but she was glaring at his half-full coffee pot.

"Seriously?" she said dryly. "You're experiencing anxiety and sleep deprivation, and your solution is coffee at 8 pm?"

"Chill. I didn't drink any of it." He collapsed on his couch and pressed his hands against the sides of his head again, trying to force the throbbing to subside.

He heard Caitlin's heels clicking against his hardwood floor and she was at his side. "Headache?"

"Not until you showed up," he muttered. "Uh, yeah. It- it goes in and out. I don't know if it's related, or coincidence-"

"It's not a coincidence," she said so firmly and confidently that he raised an eyebrow at her, surprised. "I mean, I'm guessing it's because you've been so sleep-deprived." She handed him a glass of water that she was apparently holding. "Drink."

He lifted the glass to his lips, and the water was so cold that it made his headache throb again. He reached to set it down on the glass table, but Caitlin intercepted, grasping the cup firmly. She held it out to him again. "Cisco."

He glanced at her reproachfully. "I'm not a kid. I can take care of myself."

"That doesn't mean you have to," she said softly, and he felt suddenly guilty for being annoyed with her.

She looked him over and her eyes locked with his. "How are you feeling?"

"I'm okay, Caitlin." He took the cup from her and swallowed a few sips of water to prove his point. "Really."

She tilted her head, her brown eyes thoughtful and probing. "You sure about that?"

She already knew. She could see right through him, and he hated himself a little for being so transparent. He had lied to her so many times over the last few days, and he hated how it made him feel.

He sunk his head into his hands and exhaled- slowly, defeatedly. He heard the dull clunk of Caitlin's shoes against the floor when she stood up, and felt the couch cushions depress beside him as she sat down. There was a long, weighted pause, and he knew she was waiting for him to answer her.

"Is Iris okay?" he asked in a quiet voice.

"Cisco, she isn't mad at you," Caitlin said quickly. "Nobody blames-"

"No, I mean, is she ever going to be able to use her left arm again?" Cisco glanced up at her anxiously. "I mean, I've literally knocked people out with those blasts, _metahumans,_ and that was when I was controlling them. And, well, Iris is human, and I _wasn't_ in control, it was an outburst, and it was all concentrated into one area of her body, and it could have completely shattered-" His voice cracked and he slumped forward, his heart pounding. _Ba-dum, ba-dum, ba-dum._ Too fast. Too heavy.

"Breathe," Caitlin said firmly, and placed a hand on his knee, grasping it tightly. Her touch made him feel grounded and calmer. "It was a non-displaced radial fracture. Just a crack," She traced her finger along the side of his wrist, "About there. It should heal in a few weeks."

"Is the team angry?" Cisco asked, and Caitlin bit her lip hesitantly. "Caitlin," he begged.

She exhaled. "Barry's a little angry, and so is Joe. You know how they get when Iris gets hurt." Cisco hadn't even thought about Joe. He had seen Joe's fierce papa bear come out enough times to know that he did _not_ want to be on the wrong side of that. _Ba-dum, ba-dum, ba-dum._

"Wally was at school," Cait was saying, "but I'm sure he's heard by now, and you know how protective he is of her. Iris was a little freaked out, but she's mostly just worried about you, and annoyed that all of the men in her life treat her like she's seven instead of twenty-seven, and H.R. is probably over-dramatizing it in his novel." She laughed lightly, but he knew it was for his benefit. _Ba-dum, ba-dum, ba-dum._

Cisco leaned forward and gripped his knees until his knuckles turned white. Caitlin's smile dampened and she placed a hand on his back. "Listen. It was an accident, and they all understand that. I think if there's any anger, it's just because they're scared."

"They're scared of me?" He laughed harshly. "That's comforting. Thanks for that."

"Poor choice of words, sorry. They're _worried."_ Caitlin's palm pressed gently into his back between his shoulder blades. She moved her hand up and around and down and up in a soothing, circular motion. "Cisco, they're not just our team, they're your friends. You're hurting and they _care._ I think it's the uncertainty that has everyone a little on edge, but please don't get it into your head that they are in any way against you, because we're all on your side."

He snorted derisively. "Yeah, Barry really stood by me when he cuffed me with my own tech."

"Oh, give me a break." Caitlin abruptly removed her hand from his back, and when the comforting pressure was gone, he felt like he'd had an oxygen tube ripped out of his nose and he couldn't breathe. He tilted his head at her and saw that her jaw was set in a hard line, a stark contrast from the gentle curve of her smile just a few moments ago. Her spine was straight, like a mannequin with its string pulled taut. "You created the cold gun in case Barry became one of the evil metas. We were all suspicious of Harry, and even H.R., because of what Thawne did to us." Cisco felt his hands clench involuntarily when she said _Thawne._ "When you came back from Earth-2, you were antsy around me for a week because of Killer Frost, and I think half of us have been in the pipeline at some point."

Cisco clenched his hands into fists. "What's your point?" he asked curtly.

"My _point_ is that even though we trust each other, our world is so crazy and extreme and dangerous and we've lost _so_ much that sometimes we _have_ to be on guard. When Barry cuffed you, I don't think he thought that you were going to hurt him. He thought that _Reverb_ was going to hurt him." He looked up at her quickly. _Ba-dum, ba-dum, ba-dum._ "As soon as he realized his mistake, he let you go. And I'll remind you that you were hallucinating _vividly_ and you definitely weren't stable, and Barry had no idea whether you were in control or not, but after that initial reaction, he gave you the benefit of the doubt. I think it's time for you to repay the favor."

Cisco's hands gripped his knees again and his gaze dropped to the floor. Caitlin was right. She usually was. And yet… _ba-dum, ba-dum, ba-dum._ His heartbeat rang in his ears, as if he'd held a seashell up to his ear. His muscles tensed like stone under his skin.

He could feel Caitlin's watchful gaze, searching his face, penetrating his thoughts. She reached out a hand and pushed his hair behind his ear so that she could see his face. Her fingertips brushed against the top of his ear and he trembled under her touch. She leaned forward so that they were eye to eye. "What are you thinking about?" she murmured.

Cisco stared at the floor. His head felt like it was made of lead- it weighed him down and drooped to the floor and he couldn't bring himself to meet Caitlin's eyes. He heard her voice in his ear, feeling his emotions swell and beat at his ribcage. Voices swamped his brain; they were a tepid, permeating fog. One voice rose above the din, ringing in his ears.

 _A great and honorable destiny awaits you. I hope that you'll remember who gave you that life._

Was this where Thawne's malevolent promise was realized? Was this how it began? Cisco pushed the thought down, down, down, but it grew in his chest, pressed against his heart and beat against his ribcage. _Ba-dum, ba-dum, ba-dum, ba-dum._ This wasn't the first time he'd had this thought, of course, but he'd convinced himself before that he could never be like Thawne. He wasn't sure anymore. _You're not him, you could never be, you'll never be him…_ Was the "him" Reverb or Thawne? Did it matter?

"Cisco!" Caitlin's hands grabbed his, and her freezing touch jolted him back to reality, like he'd been doused with a bucket of ice water. "Stay with me. I'm right here."

 _I'm right here. Just listen to the sound of my voice. Stay with me._

Cisco squeezed his eyes shut, trying to focus on Caitlin and tether himself to her voice like he'd done in the vortex. But this was the second time that Caitlin had repeated, verbatim, something he'd heard in a Vibe. Thawne's voice cut into his thoughts again, like a hot knife cutting through his skin.

 _You were able to retain traces of an alternate timeline… you were able to see through the vibrations of the universe._

"Cisco." Caitlin's voice was tight. She was straining to keep the panic out of her voice, but he knew her too well not to hear it. She was grasping his hands so tightly that it hurt, but he didn't move, rendered immobile beneath her touch. "Cisco, I'm the only one here in this room. You are in _this_ universe, in _this_ timeline, with me." It was as if she could read his thoughts. Maybe because she _was_ his thoughts. Maybe she was like Reverb, a manifestation of his- no, that wasn't it, but there was something- something that he was so close to figuring out, but it was just out of his reach, but he could feel it, like an assassin breathing on his neck.

"Cisco, it's like- this is like Sméagol and the ring, right? When he's in the boat with his friend, and he hears the ring whispering to him, telling him to drown his friend and go find the ring… and the voice drags him down underwater, but you don't have to let it." Her grip was really starting to hurt, but the pain made him feel present in his body again. He clung to it. Caitlin was rambling now, her voice accelerating with desperation. "Or- or like the Horcrux locket in The Deathly Hallows. If you wear it alone for too long, it gets in your brain, colors the way you see the world, makes you suspicious and angry, but if you let someone else carry the load for you-"

"So does the ring," Cisco mumbled, and Caitlin's grasp around his fingers relaxed slightly.

"What was that?" she whispered.

Cisco extracted one of his hands from her grip and rubbed the side of his head. "The ring has the same effect as the Horcrux locket. One of the many things that Rowling co-opted from Tolkien. You should have just stuck with the ring analogy."

Caitlin's eyes filled with relief, and it flooded across her face in the form of the color returning to her pale cheeks. "I have to admit, I've never actually read Lord of the Rings," she said, and smiled tentatively. "And the only time I've watched the movies is with you."

He sat up straight with mock indignance. "Girl, get out of here." She laughed and he cracked a weak smile. He pressed his free hand against his chest to feel his heartbeat. Slower, calmer. Thawne's voice was gone. Two minutes ago that would have come as a relief, but he had been on the verge of solving something. Now it was gone and it was killing him.

He turned his body slightly so that he was facing Caitlin. "How did you know to say that?" He asked.

She tilted her head to the side. "Because you're a giant nerd and I can always get through to you with fictional analogies?"

"No, not that." He pulled on his right hand, which Caitlin was still clutching with a death grip. She glanced down distractedly, as if she'd forgotten she had been holding it, and released him. He stretched his arm behind his head, feeling the warm stretch in his shoulder muscles. He dropped his arm back down to his lap and clasped his hands together pensively. "What you said about the universe, and the timeline."

"That was just off the cuff, I guess," she said brightly, and stood up. "Hey, listen, I need to- I forgot something at the lab. Are you going to be okay by yourself, or do you want to come with?"

Cisco stood up, following her every motion with his eyes in an attempt to analyze her body language. The way her eyes avoided his when she said "off the cuff". How she tensed her shoulders when she said "at the lab". The way she'd tripped over her words from "I need to" to "I forgot something"- like she was improvising an excuse.

 _She always has an agenda,_ Reverb whispered in his head.

He locked his eyes with hers to see how she would react. At first, her gaze darted to the left, but then her eyes snapped back like a rubber band, staring him down. _Defiantly?_

"Caitlin, what aren't you telling me?" He asked slowly.

"Nothing, Cisco," she said calmly. "I was researching Alchemy before I came here; I wanted to see if I could dig up anything on one of his followers that would help us. I left my laptop at work on accident." He narrowed his eyes, trying to see through her pretenses, but Caitlin was much better at guarding herself than he was. Or she really was telling the truth, and the paranoid part of him- the part that had decided his sociopathic, guyliner-wearing doppelganger was an awesome way to manifest his subconscious thoughts -was making him second-guess her. That was wrong. If he wanted to fight back against Reverb, he had to show a little faith in the people around him. That was one of the defining differences between him and Reverb- Cisco was a pack animal and Reverb was a lone wolf. _More like a hyena. Stalking, pacing, laughing…_ Forget Reverb. His biological infrastructure was shaken up by the dark matter, and the only way he could reorganize it was by focusing on the things that made him Cisco and kept him from being Reverb.

Caitlin was still gazing at him, her expression unreadable. "Okay," Cisco said finally. "Yeah, I'll be fine."

"Okay." Caitlin grabbed her coat off of the coffee table and strode back over to his front door. She glanced back over her shoulder at him, her face laced with concern again. "I'll be back soon."

He joined her at the door and opened it for her. "You don't have to come back over. Go home, get some rest."

She ignored him. "I'll be fast." She ducked through the door and Cisco pushed it closed behind her.

* * *

Caitlin made good on her promise. She was back in forty-five minutes, which was beyond impressive, because when he heard her high heels click through his front door again, she was hefting a brown paper takeout bag along with the black leather briefcase that she kept her laptop in.

"What's this?" He asked, maneuvering the bag into his arms and peeking in the top suspiciously.

"I got us Chinese because I've been working all evening, and you haven't eaten in three days and everything in your fridge is either expired or processed and full of preservatives," she said matter-of-factly, setting her briefcase down on the counter with a dull thump.

Cisco raised an eyebrow at her. "Says the pizza pocket aficionado."

Caitlin mumbled something about how they were convenient and busied herself with unloading the contents of the bag. Cisco leaned against the counter, watching her.

After a few moments accompanied only by the rustling of the paper bag and the _squeak_ of the waxy paper boxes as Caitlin handled them, he said, "You don't have to do this, you know."

She paused and turned her head to look at him. "What do you mean?"

"You don't have to take care of me like this. I mean, it's nice, I really appreciate it, thank you. But you don't need to-"

"Don't be stupid," she interrupted. She paused to fiddle with the lid of one of the boxes. She pulled the flap loose and the air filled with the aroma of chicken and rice. She looked up at him fervently. "Cisco, I can't think of a single occasion over the last four years when I needed you and you didn't drop everything to be there." She ripped off the paper covering of the chopsticks and seized a piece of chicken. She lifted it to her mouth, chewing thoughtfully. "It's funny, usually I'm the one resisting support. You don't usually have a problem with being taken care of." She tilted her head at him, her expression softening. "So what gives?"

He shrugged. "I dunno."

"That's not an answer." She pushed one of the takeout boxes at him. "Eat."

He opened the takeout box and unwrapped a pair of chopsticks. He stirred the contents of the box idly as Caitlin efficiently speared chunks of chicken and rice. The fluorescent lights in his kitchen flickered slightly above them, and the faint sound of horns honking on the street beneath them filled the silence. He knew Caitlin was waiting for him to say something, but he didn't know what to say.

"Cait-" He began, and broke off. She raised her eyebrows and nodded slightly, encouraging him to continue. He took a short, sharp inhale and forced himself to maintain eye contact. "When I broke Iris's wrist- I think I enjoyed it."

The muscles in her face twitched, but her expression remained neutral. "What do you mean?" she asked calmly.

"I don't _know,_ " he said again, frustrated. "I mean, it's not that I enjoying hurting _Iris,_ I felt bad, I was freaked out, I was worried Joe was gonna shoot me when I got back-" Caitlin snorted with laughter and he raised his eyebrows. "That's funny?"

Her face sobered and she shook her head. "No, sorry. Go on."

He rolled his fingers over the chopsticks, trying to regain his train of thought. "It was weird. It was like, I got this weird adrenaline trip from hurting her. Not hurting _her,_ specifically, but, like, it was the physical action or something-" Caitlin's forehead was creased with something in between intrigue and worry. "I sound like a psycho, don't I?"

"No, not at all," she said hastily, and set her takeout box down on the counter. "Do you think it could be because you use your powers so infrequently? Maybe activating them releases some kind of endorphin rush, but you're just not used to it because you don't use them enough."

"I thought you said there was more to this than lack of use." Cisco leaned against the counter.

Caitlin waved a chopstick in the air dismissively. "I said maybe. But even if there is, this is a part of your physiology that you've suppressed for a while, and that was dormant for even longer than that. It's like trying to run on an atrophied muscle- it hurts like hell and it doesn't work."

"What are you saying?" He leaned forward, watching her intently.

She shrugged. "That not everything is a sign that you're going to turn into an evil supervillain. Maybe you need to start giving yourself the benefit of the doubt, too. You know what kind of person you are, I do, we all do, and you're a _good_ person, Cisco. I think it'd take more than a few vivid delusions to change that."

 _How can you say that?_ He couldn't exactly blame her, since she didn't have the full story. She still didn't know about the beetle or the teenage thief, but he had no intention of telling her. "You don't know that," he argued.

"You're right, I don't," she said quietly. "But we write our own stories, remember? You literally had a Vibe of me, fighting you as Killer Frost, and I was _so_ sure that I was going to become her, but I didn't." She twisted a strand of her soft brown hair around her finger. "I still worry about it, of course. But I have faith, in myself and in my friends to help me through it. Something that you were very good at until a few days ago."

Cisco stared at the chopsticks in his hand, twisting it absently. _Should I tell her about the vibe of our fight? Should I tell her that I went to the future?_ He shook his head to clear it, an action that did not go unnoticed by Caitlin.

"You know that song in Hamilton?" she said out of nowhere. "What was it called… the one that Aaron Burr sings after Hamilton gets married." Her tone was too conversational, like she was trying to ease his mind by babbling. "The one that you think is going to be a sob story to justify him sleeping with a married woman and killing Hamilton, but instead turns out to be a surprisingly nuanced and complex-"

"You mean 'Wait For It'?" he inserted, cutting across her banter.

She nodded. "That's the one. Remember, near the end of the song, he says, 'I am the one thing in life I can control.'" She paused, raking her chopsticks through the rice pensively. "I had that line in my head the other day, and I just thought, maybe we should start thinking more like that. It feels like there's always something bigger than us and stronger than us- Zoom, Alchemy, the speed force even- and every single day it gets more complicated, what with foreknowledge and all-"

 _You really have no idea,_ Cisco thought dryly.

"-and every day, we learn something new that makes the universe seem even more vast and scary than before," Caitlin was saying. "It feels like we're pawns sometimes, like we might inevitably become-" Her breath caught in her throat. "You know," she said quietly, glancing down at the inhibitors on her wrists. "But that doesn't mean we should give in. At the end of the day, the only thing that we have complete and total control over is ourselves."

He cocked his head quizzically. "When did you become cultured enough that you started making surprisingly relevant Hamilton references?"

"How could I not? You've played the soundtrack at work, like, fifty times."

More than that, Cisco was sure. Caitlin was watching him again.

"You okay?" she asked.

He nodded. "Yeah. Just exhausted."

"I don't blame you." She tapped the side of the takeout box he was holding. "You can sleep after you eat half of that."

"Cait," he groaned, but she was insistent, and after a few minutes of her harassing him, he started eating the stupid rice and chicken just to get her off of his back, and he realized how hungry he actually was. Also, it was really freaking good Chinese. He ended up eating the whole serving, much to Caitlin's smug triumph. He told her he was going to take a shower, so he left her in the kitchen and went back into his bedroom. He entered the bathroom and closed the door, finding himself face-to-face with his own reflection. Haggard, pale, and unshaven for who-knew-how-long. He stared into the eyes of the reflection, as if he could see into his own eyes and figure out what he was thinking. He had been _so_ close earlier, but it was hanging just out of his reach.

He switched the bathroom fan on so that Caitlin couldn't hear him. He took a deep breath, summoning all of his courage, and whispered, "Reverb."

He waited a few moments, expecting the gloating voice to respond to him, but the only sound was the whirring of the bathroom fan. "Reverb," he said, louder. Nothing. _Dammit._

After a few more unsuccessful tries, he took a shower- all cold water, it made him feel awake and present in his own body -and by the time he had dressed, the whir of the bathroom fan was grating in his head, so he switched it off. He was toweling off his hair when he heard Caitlin's voice drifting in from the living room.

"-yes, of course," she was saying. "I'll send you the results as soon as the tests are finished, but it'll be a few hours still. I barely got away long enough to start them earlier."

Cisco cracked the bathroom door open and moved quietly into his bedroom so that he could hear her better. He stood just inside of the door, listening intently.

"No, of course I don't," she said angrily. "Besides, I don't remember asking your opinion. I called you because I'm stuck, and you're the best scientist I know." She paused. "And… Cisco needs to see you. He misses you." Cisco raised an eyebrow. Definitely talking about him, then. "He needs you to talk some sense into him. He's letting all of this get to him and he's only a beard away from out-Oliver-Queen-ing Oliver Queen." Cisco winced. That was… slightly hurtful.

"I told you, there's no way that it's just psychosomatic," Caitlin was saying. "I thought that at first, too, but I gave him fifty milligrams of quetiapine and he was still-" She broke off, as if whoever she was talking to had interrupted her. Cisco made a mental note to look up what the safe dosage for quetiapine was. "No, I didn't do an EEG. No, I didn't do a PET scan either, because I didn't want to make him hyper-focus. He already thinks something is really wrong, and I didn't want to affirm his anxieties and make it worse." Another pause, and Cisco felt his chest constrict. Caitlin did think something was wrong, despite her telling him not to worry.

"Yeah, well, there's a reason you're a scientist and not a therapist," Caitlin said dryly. "Emotions never were your forte. Despite your PhD in psychology and six other areas."

Was she talking to…? _No. That's not even possible._ Cisco inclined his head slightly so that he could hear better.

Caitlin fell silent, and the pause was much longer this time. When she spoke, all she said was, "Okay, I'll call you back when he falls asleep." Cisco felt his muscles seize up involuntarily. Caitlin sighed and then said, "Yeah, I know. Thanks, Harry."


	9. Chapter 9

Cisco slumped against the wall, Caitlin's words ringing in his ears _._ She was talking to Harry. _How? I've tried everything I can think of to transmit cellular signals between Earths, but the signals always get muddled because of the change in frequency…_ Caitlin was brilliant, but this was his area of expertise, not hers, and even he couldn't figure it out.

But more importantly, she was hiding something. She had run some kind of secret test on him, probably while he'd been sleeping in the med bay. She had mentioned contacting Harry before, so the fact that she had done it without telling him meant that she didn't want him to know about whatever Harry was helping with.

More importantly than that- Cisco had suspected Caitlin, and trusted her anyway, but it turned out she _was_ up to something _._ Was Barry in on it, too? Were they conspiring against him? _She always has an agenda,_ Reverb's voice said. Maybe Reverb knew what he was talking about.

He shook his head vigorously. _Stop thinking like that._ He went back to the bathroom and ran a comb through his hair, attempting to calm down, but he couldn't stop overanalyzing Caitlin's behavior from that whole evening. He had felt so comforted and safe with her there, but this new knowledge had poisoned everything. Is that why she'd been so adamant about staying with him- not because she was concerned, but so she could run secret tests and try to prove her hypotheses? She had probably swabbed his DNA off of that cup of water she'd been so insistent on, and she insisted on him eating probably so that she could run a blood test without him passing out. Or- maybe she had drugged him. He felt his stomach twist with dread. Was she just waiting for him to pass out so that she could lock him in the pipeline? He didn't feel loopy or anything, but if she'd wanted to sedate him, she would have used something slow-acting, so that he wouldn't suspect anything.

"Shut up," he said aloud, clenching his fists. This wasn't him; he didn't think like this. "Get out of my head, Reverb." Caitlin was right, it was just like the Ring, tainting his thoughts and deluding him. But he was right to be wary- she was clearly hiding something, and this wouldn't be the first time that she had lied about something to protect him. The whole team had at some point, himself included, but that didn't mean it was justified. She was withholding the truth about something that directly affected him, and that wasn't okay, because it wasn't her decision to make.

He pulled his hair back and stared at himself in the mirror. He shouldn't confront Caitlin about it yet, because if she didn't want to tell him before, nothing would have changed. And if he was wrong, he didn't want her to think that he was being paranoid. He needed to catch her in the act of something, so that his suspicions would be clearly justified. She had mentioned that she was running tests back at the lab, so she would have to go back at some point to check on them, so he could follow her then. Until then, he needed to act normal. _Which should be easy, because lying to friends has become a pastime at S.T.A.R. Labs. We should all put it on our resumes under special skills._ He pressed the thought down and walked slowly into his bedroom. He paused, listening, but all he could heard was the _click-click_ of Caitlin typing. He took a deep breath and opened the bedroom door.

Caitlin was sitting on the couch, her long legs tucked primly underneath her, typing away at her laptop. She looked up when she heard the door opening and smiled.

"Hey," she said brightly.

"Hey." Cisco tried to keep his tone and expression neutral. He wandered over to the couch and sat down beside her. He expected her to hastily close her laptop or switch pages, but she was looking at Julian's journal article about the Philosopher's Stone. He decided to prod her to see how much she was willing to lie. "Who were you talking to?"

"What?" she asked distractedly.

"I heard you on the phone or something," he said casually.

"Just Barry," she said evenly. That was typical Caitlin. She chose a lie that was too generic to be refuted and that Barry might even verify, because it was normal-sounding enough. "Are you feeling tired at all?"

"No," he said, too defensively. "Why?"

Caitlin stopped typing. "Because," she said slowly, "you've been experiencing severe insomnia for weeks and you said you wanted to get some rest." She looked at him over the top of her computer screen and frowned. "You okay?"

Crap, she was on to him. He rubbed the side of his head, as if it were hurting still. It wasn't. "Yeah, I guess. Y'know, given the circumstances."

He must have been convincing, because her shoulders relaxed and she set her laptop down on the coffee table. "You should at least lay down," she advised. "You'll never fall asleep if you're not trying."

The thought was tempting, but he remembered what she said to Harry- _"I'll call you after he's asleep."_ Which meant that she was planning on sticking around until then, and even though he wanted to give Caitlin the benefit of the doubt, he didn't want to make this little scheme any easier for her.

"I'm really wired, Cait," he said, which was the truth. "I took a pretty long nap and woke up at seven. I don't think I'm sleeping any time soon. If you want to go home, though-"

"No," she said, too quickly. "I don't mind being here with you, Cisco. Please don't think that I do." She paused. "Unless you want me to go?"

Did he? Yes, she was obviously up to something, and if she went to the lab he could follow her. Then again… there was a chance that whatever she was up to was benign and just out of concern for him. And after the last three days of anxiety and hallucinations and general freakiness, the only times he had felt safe was when Caitlin was there. If she left, maybe Reverb would show up again, or he'd start losing it and exploding things. He didn't want to find out.

He reached out and placed his hand over hers, just briefly. She squeezed his hand, and her soft touch against his hands made his heart skip a beat. He jerked his hand back sharply. Caitlin glanced at him quickly, clearly hurt.

"Sorry," he said hastily, trying to cover how flustered he felt. "I'm… kinda iffy about skin-to-skin contact right now. Because of Iris."

She bit her lip. "That's fair." She folded her hands in her lap and clasped them together. "You didn't answer my question."

"What?" he asked blankly. He had been so distracted by the way her touch made him feel that he had lost track of the conversation.

"Do you want me to go?"

Oh, that. "No, I don't. I really don't, actually. You're, uh, way better company than Reverb."

The corners of her eyes crinkled with a smile. "I would hope so."

There were a few beats of silence. No matter what anybody said about golden silence, this was… awkward. There was too much baggage right now to be able to enjoy mutual silence.

Thankfully, Caitlin broke it. "Hey, if you don't think you can sleep anyway, we haven't had a movie night in a while."

That was a great idea, actually. It gave him a reason to put off sleeping for another few hours, it would distract both of them, and it would create some sense of normality. Just the two of them, hanging out in his apartment, watching a movie. He needed to forget about everything for a little while, because if he didn't it would drive him to the edge.

"You're right. We should fix that right now." Cisco kicked his feet up onto the coffee table and reached for the TV remote. "What's that one where J-Law and Chris Pratt get stuck on a spaceship for ninety years? Or we could watch Lord of the Rings to celebrate your achievements in pop culture references."

"I think it's my turn to pick, actually." Caitlin snatched the remote out of his hand. Her fingers brushed against his and he felt the hairs on his fingers stand up. He crossed his arms against his chest so that their hands would stop accidentally touching.

"Who says it's your turn?" he demanded. Caitlin's movie choices bored him to tears, at best.

"Last movie night, we watched The Conjuring. Does that sound like something I would pick?"

"I only picked it because you're cute when you're scared," he teased, and instantly felt his face heat up. _Freudian slip?_ It wasn't, it was a joke- Caitlin didn't get scared during movies, just commented on the bad special effects and scientific inaccuracies. But the cute part, that wasn't a joke. He just hadn't meant to say it out loud.

Luckily, Caitlin didn't notice, or didn't care. "You screamed eight times," she retorted, clicking buttons to navigate the screen to Netflix. "Anyway, I watch your movies all the time. Don't you trust my judgment?"

"In life-or-death situations? One hundred percent. On movie night? No way."

She frowned at him. "Just for that, we're watching a National Geographic documentary."

He curled into the corner of the couch as Caitlin flicked remote buttons to select some remarkably banal documentary. At least if he was listening to some white dude drone on about the Grand Canyon, he wouldn't have to worry about hearing Reverb.

It also meant that Caitlin was right next to him.

And that meant he was safe.

* * *

Caitlin barely paid attention to the documentary; after all, she'd seen it twice. Instead, she focused her attention on Cisco. Caitlin watched his face carefully to see if he looked like he was spacing out, but his eyes flickered back and forth every few seconds. He only lasted a few minutes before he got out his phone, tapping the screen idly- some dumb Japanese cat game. Once every few minutes, he would glance sideways at her, and she pretended not to notice, so that whatever anxieties were racing around in his head would stop. Eventually, he put his phone down, and rested his head on the arm of the couch. She watched his head droop forward and his muscles relaxed. His breathing was regular, shallow and even.

"Cisco?" she asked, quietly, but he didn't stir. He was out. Good. Even if he had managed a decent nap earlier- which she didn't believe -he had weeks of sleep to make up for, from the sound of it.

She stood up, slowly, so that she wouldn't wake him up, and picked up her briefcase, which laid on the coffee table. She found the phone- not hers, the one Harry had given to her, and that had some sort of external tech attached to it that made it look more like a Doctor Who prop. She walked quietly into the kitchen and dialed Harry's number- apparently on Earth-2, standard phone numbers had 12 digits.

After a few staticky rings, he picked up. "There you are, Snow," he said, his voice only slightly less gruff than usual. "What took you?"

"It wasn't that long," she said defensively. "I had to wait for Cisco to fall asleep. Frankly, it's a miracle that I got him to sleep at all, let alone in under an hour."

"Would've been faster if you drugged him."

"Harry!" she said angrily.

"I'm kidding, Snow. Somewhat. It doesn't matter. How's Ramon holding up?"

She paused. "I'm surprised you asked about that before asking me about the test results."

"You know I care about him," he said roughly, and she realized that she'd hurt his feelings.

"Sorry. He's not good, obviously, but I think he feels better when I'm here."

"I'm glad you came to that conclusion after letting him suffer by himself for days on end."

Caitlin felt her cheeks flush with anger at the accusation. She was trying her best to help Cisco and she didn't need to deal with this. She inhaled deeply, remembering that blunt criticism was Harry's way of disguising emotions. "Harry, if all you're going to give me is criticism, then I don't need your help. I'm trying my best."

There was a beat of silence. "Of course you are," he said, and his tone was softer. "How about those test results?"

"Still back at the lab. I haven't gotten a chance to look at them yet, I told you that earlier. I only called because you told me to call you as soon as Cisco was asleep."

"Right. I assume you haven't done an EEG yet?"

Caitlin breathed a sigh of exasperation. "I told you, I don't want to run tests on him without his permission."

"You did an EKG without his permission."

"That was a fairly standard procedure. This feels more invasive than that."

"How is monitoring his brain any more invasive than monitoring his heart?" The sound of his voice crackled; the signal wasn't very strong.

"It is, and you know it," she shot back.

"Snow," he said abruptly, and his tone made her fall silent. "Do you want to help him or not?"

"We wouldn't be having this conversation if I didn't."

"Then for the love of everything holy, do the EEG! We need to see exactly what his brain does while he's hallucinating."

"His hallucinations stopped a few hours ago."

"According to him."

"No, I can tell when it's happening. He gets really agitated and he usually talks back to the delusion." She folded her arms. "And you need to stop questioning my judgment, Harry. Besides, if I wanted to monitor his hallucinations, it would have to be while he was awake."

"Then tell him that you just need to run a scan, and that it's not a big deal-"

"-because nothing says 'not a big deal' like an invasive brain scan."

He sighed, frustrated. "Then tell him the truth."

"I thought we agreed that we weren't going to tell him until we have an actual theory, not just hunches."

"There was no _we_ involved in that decision."

"I just don't want to scare him."

"He's not a child, Snow. He doesn't need you to shield him from reality."

"You haven't seen him lately," she argued. "Or at all, really, the last six months. He's different than he was when you were on this Earth. He's…" She glanced over at Cisco, curled up on the couch. "Unhappier." That was an understatement. "And the last few days just made it worse."

"I respect Ramon far too much to coddle him. I thought you felt the same way."

"I do," she said quickly. Did she? Of course she respected Cisco, of course she knew that he could handle himself, but she couldn't stop worrying about him. Cisco was usually the optimist, he of the sunny smiles and impeccably-timed wisecracks- even when he was feeling down, he always put a good spin on things. Then Dante died, and something inside of Cisco broke. _And some things that are broken can't be fixed._ Her Killer Frost episode had been all kinds of traumatizing for her, but what she remembered most clearly from that awful night was the look on Cisco's face when she had called him pathetic. Like he'd been punched, no, like she'd stabbed him, and twisted the knife in the wound. She knew that he didn't hold it against her, but she did. When he'd been so clearly not okay these last few days, and he'd asked for her help, she'd jumped to take care of him. That was how Caitlin dealt with guilt, by tidying up and trying to mend the things she'd broken.

"Still there, Snow?" Harry's voice cut through her thoughts. The sound of his voice was rough with bits of static.

"Yes," she said quickly.

"Are you going to go back to the lab and check on the EKG results?"

Her eyes drifted back to the couch. Cisco had turned over in his sleep, but aside from the even rise and fall of his chest, he was completely still. She didn't want to leave him, but if she was quick, she could probably get back before he woke up.

"Yeah," she said finally. "I'll let you know what I find out."

"Okay," he said. "And will you consider being honest with him?" His voice sounded weary, tired. Caitlin wished she could see his face and see what he was thinking.

"I'll think about it," she said, and then added firmly, " _if_ he's feeling better tomorrow."

She heard him breathe a sigh. "Okay," he relented. "Only call me back if you see anything alarming on the test results; I'm having trouble hearing you on this thing. I think the signal is getting weaker. I'll have to take it apart to see what I can fix."

"I'll let you know," Caitlin said, and hung up before he could say anything else. She went back over to the couch and picked up her briefcase, tucking Harry's inter-dimensional cellular device safely inside. She glanced at Cisco, who was still aside from his slow breathing. He looked so young and vulnerable in his sleep. Harry was right, she needed to tell him the truth, and she would- she just wished that the truth didn't have to hurt him any more than he already was.

She picked up the white throw blanket hanging on the back of the couch and draped it over his body. "I'll be right back," she whispered, and walked quickly to the door.

* * *

 _"That'll be all, Mr. Ramon, thank you."_

 _The detective walks away and I am left alone, shivering in the freezing January night. I look around the crowd of cops with notepads and medics carrying stretcher and- my stomach lurches when I see two medics hauling a body back. I wonder who's in the bag- Tony from physics or Maeve from the bio lab? Or Hartley, or Dr. Wells, or Caitl-_

 _"Cisco," a quiet voice says behind me, and I turn around._

 _Caitlin Snow is standing barefoot on the wet pavement. She's holding one broken high heel in her hand, who knows where she lost the other one. Her skin is paler than usual, and I can see the purple and blue webs of her veins beneath her eyes. Her face is dry, but her eyes are slightly bloodshot, like they've been open for too long. She has a cut on the side of her face, but the blood coagulated already._

 _"Hey, you," I say weakly. She doesn't smile. She doesn't frown either. She doesn't even look sad. Her face is blank- not stiff, like when she's guarding herself, just empty. Hollow._

 _"Did you get checked out by a medic yet?" she asks._

 _"No. Did you?"_

 _"I don't need to. I'm fine."_

 _She's definitely not fine by any standard. As for physical injury, I notice she's cradling her left wrist against her body, her hand hanging at a slightly awkward angle._

 _"How about that wrist?" I ask._

 _She glances at it. "Fine," she says brusquely. "You should go get checked out. You hit your head pretty hard."_

 _I reach out and tap her wrist gently. She gasps in pain and jerks her wrist away._

 _"Fine, huh?"_

 _Her eyes narrow. "Go find a medic, Ramon."_

 _Hearing her use my last name stings, but I push that away. "Caitlin. I understand how you're feeling, but you need to take care of yourself."_

 _"Please don't pretend to know how I feel." Her voice wavers and cracks. "You have no idea how I feel right now," she says through gritted teeth._

 _I feel my eyes tearing up. If I can just make it through this night, if we can just make it through this one night of hell then we can move on to tomorrow- but there's nothing to move on to. Several of our coworkers are dead, all the rest are injured, and the shining promise of S.T.A.R. Labs is smoldering to the ground. The dark night is lit by the glow of the still-not completely extinguished flames._

 _I take a step towards Caitlin. She doesn't move, so I take another step, and slowly place one arm around her shoulders. She stiffens under my touch, but doesn't move. I close my other arm around her and pull her to me. Her legs buckle beneath her and suddenly we're both on the ground. Caitlin is crying and I'm crying and I'm holding her and the world is spinning. She collapses against my body and her head drops into my lap. I run my hands through her soft brown hair, over and over and over. Her wracking sobs shake my body and I can feel her pain._

 _"Ronnie's gone," she chokes out, and I feel my chest constrict. Ronnie is gone forever. Because of me._

 _"I'm so sorry," I say, but my throat is tight and tears are running down my face. "I'm so sorry, Caitlin. I'm so, so sorry."_

* * *

"Caitlin," he shouted frantically, and reached out for her, but she wasn't there. Cisco opened his eyes and his senses kicked in.

 _I'm on a couch. My couch. In my apartment._

 _It's 2016. That night was years ago._

 _Breathe._

He leaned forward and rested his head in his hands. He felt moisture on his fingers and realized that he had actually been crying. That dream was too vivid.

Except it wasn't a dream. He sat up abruptly. Aside from his one weird Reverb dream, this was the first dream-Vibe he'd had for weeks that wasn't about Dante. But there were similarities- it centered on someone he cared about, on a night of devastating loss.

He ripped his fingers through his hair, thinking. What did it mean? Reverb had tried to manipulate him into saving Dante- well, his brain had. Reverb was just a figment of his imagination. He had to remember that. The dreams about Dante were obviously a ramification of his guilt. Even though the particle-accelerator explosion would always be a devastating night, it was years ago, and the wounds it caused were largely healed.

Only- the Vibe hadn't been about Ronnie or anyone they'd lost that night- it had been completely focused on Caitlin.

What did that mean? It meant he was worried about Caitlin. Worried about losing her, which made sense, because she'd been the only thing keeping him together the last couple of days. But-

He lifted his head and looked around his apartment quickly. Caitlin was gone and so was her briefcase. She must have gone to the lab. He stood up and went into his bedroom to find his phone- it was 11:46. He'd slept for a couple hours at most, which meant that Caitlin couldn't have made much progress with whatever she was up to. He shoved his black Converse on and threw his coat on over the sweats he was wearing. He was reaching for his keys when he remembered that he didn't have to.

 _Open a breach._

He held out his hand and hesitated. He shouldn't be doing this, and without his gauntlets and his glasses-

 _They're a crutch. You don't need them._

He felt his hands charging up with energy and he took a deep breath, imagining the lab. He felt the energy race out of his fingertips and the atoms of the universe disintegrated, leaving a purplish-blue void. He stepped through, focusing on the lab still, not on Caitlin, not on Harry-

He felt a brief pulse of energy and for a split second, he could see the vortex around him- but then his feet were on solid ground and he was in the Cortex.

It was empty. The lights were all off except for in Caitlin's lab. He could see her, silhouetted by the single light in her lab, leaning over her desk. He heard her voice floating through the thin glass walls, but he couldn't make out the words. He walked quickly and pushed the glass door open.

She was holding something up to her ear- it looked like a phone, but it had all kinds of wires on the outside. She was staring at something on a screen, wavy black lines on a white background- _maybe test results of some kind._

She didn't notice him, so he stood in the doorway. "I told you, I'm not doing an EEG!" she was saying, angrily. "Harry, I told you, I don't want to do anymore tests without his-" She broke off. Cisco tiptoed forward. "Well, why don't you just come here if you think I can't handle it?" She spat. "Of course I care about Cisco, how dare you-"

That was enough. Cisco cleared his throat loudly, and Caitlin jumped. Her eyes darted wildly to him and she froze.

"Harry," she said, her eyes wide, like a cornered animal. "I have to go." She hit the screen of the phone and placed it down on her desk. She stood up and turned to face him.

"Cisco," she said, not meeting his eyes. "What are you doing here?"

He folded his arms. "I was about to ask you the same thing."


	10. Chapter 10

Caitlin stared back at him for a moment, frozen, and then sat up straighter, shuttering her eyes to him.

"Are you okay?" she asked anxiously. "Did something happen? Are you hallucinating again?" He raised his eyebrows nonchalantly. "What's going on?"

"You tell me." He folded his arms.

She stared back at him incredulously. "What are you talking about?"

"Why don't you ask Harry?" Caitlin's eyes widened, and Cisco peered at her to decipher the expression in her eyes- Panic? Anger? -but she composed herself in seconds. He decided to poke the hornet's nest again. "Or, better yet, skip the middleman and do an EEG so you can see right into my thoughts?"

Caitlin twitched apprehensively. "First of all, that's not how an EEG-"

"Caitlin!" he growled, frustrated. She tensed up, startled by his aggression. He sighed, trying to calm down. Fighting wouldn't get them anywhere. "Please. The truth."

Her nostrils flared slightly and she crossed her arms. "Right, because you've been so honest with me lately," she said hotly, and that stung, because he knew she was right.

He took an inhale. Long, deep yoga breaths. Wax on, wax off. "But I came clean eventually," he said coolly. "So."

Caitlin stared at him blankly, chewed her lip for a second, and then kicked the ground so that the chair she was in swiveled to face him.

"It's not what you think it is," she began, reluctantly.

"I have no idea what I think, so you probably shouldn't lead with that."

Her eyes darted around nervously, like a cornered animal looking for an escape route. _She's evaluating the repercussions of what will happen if she tells me about her little scheme. Or trying to think of another lie to tell me._ Instead, the muscles in her face relaxed, and she leaned forward, still holding a fair amount of tension in her arms and back. "Where should I start?"

"I have several questions." Caitlin nodded, permitting him to continue. He took a short breath. "First of all, how; secondly, why; and third, _how the everlasting hell_ did you manage to tweak a phone to bypass the vibrational outputs of the Multiverse?" Her face twitched, as if it amused her that _that_ was what he wanted to know. "Seriously, I've been trying to do that since last year, when I realized Harry was definitely going to leave us at some point, and I've been tinkering like crazy- or was, until I gave up. All I have to show for it is a pile of jacked-up Nokias in my workshop."

Caitlin picked up the weird phone-thing and turned it over. "Harry gave this to me the first time he and Jesse left, after we defeated Zoom." She handed it to him, and he gazed at it, slightly awestruck. He turned it over in his hands, tracing the wires with his fingers, trying to make heads-or-tails of what it was or how it worked, but that was typical Harry, always two intellectual lightyears ahead of them. He handed it back to Caitlin, but made a mental note to steal it later so that he could take it apart and try to replicate it.

"Why did he give it to you?" he asked, looking up at Caitlin. "Why not me, or Barry, or all of us?"

"Harry said to only use it for emergencies," Caitlin said, and carefully set it back down on the table. "Metahuman emergencies. And I was the only one without powers, at the time." Cisco felt the blood drain from his face as he realized what she was saying. "He gave it to me to-"

"To protect you," Cisco murmured, and felt cold all over. Caitlin nodded solemnly. It made total sense, because Harry had seen the even more harrowing ramifications of Zoom's reign, and he'd been face-to-face with Reverb.

Caitlin was studying his face, reading him. "It's not like that," she said hastily. "I don't think he had any real concerns; it was more of a fail-safe. You know Harry, he always has a contingency plan." She fidgeted with her hands uncomfortably.

He had to stomp on the urge to say _And so do you._ He took another deep breath- wax on, wax off. "Okay. So that brings us to _why."_

She folded her hands in her lap, as if that was the only way she could keep them still. "I called Harry yesterday because I was concerned about how your powers were affecting you, and I needed a second mind." Caitlin turned back to her desk and gathered a few papers from its surface. White papers with black bumpy lines- the EKG? "When you passed out the first time, I drew some blood and ran standard analysis, because we had no idea why you passed out and I wanted to make sure you didn't have any major medical issues that we weren't aware of." That was how she had known he was dehydrated, he realized. "You had fairly high levels of troponin in your blood- that's protein from your cardiac muscles."

"Isn't that a sign of a heart attack?" he interrupted. He may not have gone to med school, but he'd watched enough episodes of Grey's Anatomy to know what the signs of a heart attack were.

She nodded. "Yeah. I did an EKG, but it came back normal, and your vitals were normal, so I dismissed it as an anomaly. Then that night, when you came through the breach into my apartment, your heartrate was _way_ too fast. Any other person would have had a stroke before their heartrate got that high, so I realized that it must have something to do with your powers. When you were asleep in the med bay this morning, I did a polysomnogram to see if you went into REM- like you have in the past, remember, before we even knew you had powers we induced REM so that you would Vibe-"

"But you gave me a sleeping pill," he inserted. "Wouldn't that affect the outcome?"

She shook her head. "I gave you a placebo, but you never went into REM, anyway."

He leaned against her desk. "What exactly is your theory?"

"I was getting to that." She glanced down at the papers in her hand again. "In your apartment earlier, when we were talking, you went into some kind of trance. I'm not sure if you were hallucinating, or blacked out, but you definitely weren't all there. And you've been losing a lot of time the last few days, right?" He nodded slowly, unsure of where she was headed. "Well, I think… you know how when I activate my powers, I switch personas? I think something similar might be happening to you."

His throat was suddenly very dry and his stomach twisted unpleasantly. "What do you mean? That I'm turning into him?"

He expected her to hastily deny it, offer some scientific explanation and reassure him. She didn't. Instead, she bit her lip.

"Not exactly. I don't have enough information yet to be sure, but I think something is triggering you into a split persona, like how I start acting like Killer Frost when I use my powers. It would explain the lost time, and why you've been aggressive towards me and Barry, and why you hurt Iris."

Cisco clasped his hands together tightly, like he could hold himself together with pressure alone. It would explain everything, she said. But would it? He had been conscious and aware when he hurt Iris- he had wanted to do it. Then again, he had been pretty deluded the last few days, so anything was possible, and it would certainly be easier on his conscience if it was an alternate personality taking over. Still, it didn't quite add up.

"It's just a hypothesis," Caitlin was saying. "Which is why I didn't tell you, because I didn't want to worry you or risk confirmation bias."

 _Then why tell me now?_ He wanted to say. _What's another lie on top of all of the other's we've told?_ Instead, he clasped his hands tighter and blew out a deep exhale. "So where does Harry fit into all of this?"

"I called him for a second opinion, but I'm starting to think that was a mistake because he has _so many_ opinions." She looked and sounded exasperated. "He wanted me to do an EEG while you were hallucinating so that we could see how your brain activity changed. That would tell us if you really were switching personalities. But I didn't want to do that without your permission. It felt…" She was playing with her hands again, intertwining her long, slender fingers and then pulling them apart. "…wrong."

He waited for her to go on, but she didn't. He let out another deep breath and turned to face her.

"I understand why you didn't tell me at first," he said slowly. "I know that the unstable-grieving-psycho-burnout thing I've had going on doesn't exactly inspire confidence. But, uh, I think if we've both learned anything from the last few days, it's that lying to each other doesn't get us anywhere. Can we both promise to be honest with each other going forward?" Her gaze dropped to the ground. He grabbed her hand and she looked up at him, startled. "Caitlin, please, this is important."

She took a short breath. "What if it's something that I really can't tell you? If I had told you this before, you would have reacted badly, which was why I didn't tell you. What if it's something like that?"

She had a point. What if she had told him while Reverb was still doing his creepy spirit guide thing? That would have been disastrous. He paused, considering it. "Then you can say, 'Cisco, there's something I can't tell you right now, but I will as soon as I can."

Her eyebrows shot up. "And you'd buy that?"

"Absolutely." Cisco nodded firmly. "Trust me, I know that telling the truth isn't always the best policy. I just need to know that I can trust you and that you trust me."

Caitlin bit her lip and then nodded. "Okay. But you have to promise me that you'll do the same thing."

"Okay." He breathed out an exhale. "I promise to tell you the truth, even if… even if it scares me." He swallowed, hard.

She smiled tentatively. "No more lies?"

He nodded. "I promise." He dropped his gaze to the ground. Did that apply to all of the things he still hadn't told her? It would probably do more harm than good to tell her about how much he'd enjoyed hurting people, and about his Vibe to the future, but how could he promise not to lie when he was still withholding the truth? He rested his head on one hand and closed his eyes. His migraine was returning.

"Hey." She squeezed his hand and he felt all of the nerve endings in his arm light up. He hadn't realized he was still holding her hand. "We're going to figure this out, okay? It's going to be fine."

"Yeah, I know," he said, but he didn't feel convinced.

Her eyes were searching his face again. He was starting to hate it. She could see through him so easily, and he hated that he was so transparent.

"You're exhausted," she said, and it was a statement, not a question.

"So are you," he pointed out. Her face looked pale and drawn under the dim fluorescent light, and the lines on her forehead were more pronounced than usual, like they'd permanently creased from her worrying so much. "You should go home and get some rest."

"I'm not going anywhere without you," she said firmly. "I don't want to leave you alone. If I'm right-"

"If you're right, you shouldn't be anywhere near me," he said, and he felt his face growing hot. He stepped back reflexively. "You haven't seen what Reverb can do-"

"You're not him." Caitlin stepped forward and reached for his hand, but he pulled it away. Her brow furrowed into a hard line with frustration. "This is why I didn't…" She trailed off and shook her head. "This is just a hypothesis, remember? Nothing's positive. I could be way off base about this. And even if I'm right about the split personality, that doesn't mean you're _turning into_ Reverb. We can learn how to deal with this, just like I'm dealing with… _her."_ Her eyes went unfocused for a moment and she shook her head again, as if trying to clear it. "It's been a long day, for both of us. Maybe we just need to get some rest and regroup in the morning."

"Yeah, I'm gonna sleep real well after finding out that I have my psycho doppelganger in my head." Cisco rested his head in his hands again, pressing his fingers against his aching temples. "If there's even a chance that you're right, I shouldn't be sleeping. Lowering my inhibitions is the last thing I should be doing."

"I'll get the spare cuffs, then," she said, as if it were the most obvious thing in the world. "You're already sleep-deprived. Besides the fact that I don't want you torturing yourself, we'll get the best results on brain scans tomorrow if you're well rested."

"Alright," he relented. "I can't promise that I'll actually sleep, though."

"That's okay." She reached out and touched his wrist lightly. He felt his breath catch in his throat, but didn't jerk it away. Her fingers still made his skin buzz with electricity, but her touch made him feel grounded and safe. "Let's get the cuffs and go."

He nodded and followed her out into the Cortex. He waited as she searched for the cuffs and gathered her briefcase and coat. She handed him the cuffs and they latched automatically around his wrists. Her eyes met his for a moment, and there was a flash of emotion that he couldn't place. If only he could read Caitlin as easily as she read him.

"Ready?" she asked, and he nodded again. "Good. Let's go home."

He didn't point out that she'd referred to his apartment as _home._

* * *

It was after midnight when they got back to his apartment, and Caitlin looked even more exhausted than he felt, but she insisted on spending the night with him. She refused to leave him, even briefly, so he found a clean t-shirt and an old pair of sweatpants for her to borrow.

When she emerged from the bathroom, her clothes folded neatly in her arms, her hair was brushed smooth and her face clean. She looked even more tired without makeup on, but she still looked beautiful. Caitlin was just one of those people who glowed with natural beauty. She didn't need the makeup.

"Do you think you'll be able to sleep?" she asked. "I can stay up with you if you want. We can finish the documentary or watch something else or-"

"I'm fine," he interrupted, and she raised an eyebrow. "Okay, not fine, but I think I'll be able to sleep at least for a few hours. I promise I'll wake you up if anything freaky happens. You get some rest, okay?"

She nodded gratefully. "Okay. Good night, Cisco."

"Good night, Caitlin."

He pushed his bedroom door closed behind him, but not all the way. He didn't want to be completely cut off from Caitlin. He collapsed on top of his covered and burrowed his face into the pillows, feeling his head begin to throb again. He didn't tell Caitlin that his headache had returned because he didn't want any more drugs, and he didn't want her worrying any more than she already was. He was pretty sure that the headache was just a result of lack of sleep and the stress of the last few days.

Which brought him to the task at hand. He needed sleep and he needed it now, but closing his eyes somehow made them ache more, and he was afraid that if he fell asleep, Reverb or Thawne would creep back into his head. He rolled over onto his side and fumbled for his phone and earbuds on the side table. He searched through his iTunes for a few minutes before selecting the _Light in the Piazza_ overture. Comforting, melodic white noise. He hit "repeat one", closed his eyes, and pressed his head down into the pillow.

He didn't sleep, but after a few minutes, his mind cleared and he felt his body relax. He could see all of the colors that lurked just out of the corner of his eye, dancing clear in the line of his vision. His headache melted away and his body felt weightless.

* * *

 _"In many ways, you have shown me what it is like to have a son."_

 _Wells is standing in front of me, and his hand begins to vibrate as he raises it toward my chest. Except I know he's not Wells- he's Thawne. I've lived this before. I know how this goes._

 _I wait for his hand to sink into my chest, but it doesn't happen. Instead, I feel energy surge from my fingertips, and Thawne flies backwards. I have him pinned to the ground under a blue beam of light, and I can feel the vibrations of his body- the pulsating of his heart, the flow of his blood, the rise and fall of his lungs._

 _I can feel each one of his organs beating and vibrating and pulsing, and I could shatter each of them in an instant._

 _And I want to._

 _"Cisco," he gasps, his eyes wide, and suddenly, he looks nothing like I remember. He looks afraid. Terrified, even._

 _"Sorry, wish I could return the sentiment," I say. "But if you're a father to me, then you're a really crappy one."_

 _My face burns with anger as I remember everything Thawne's done to me. Everything he's done to the people I love._

 _I feel a wave of energy pulsing through my arms and down to my fingertips, but this time, I'm controlling it. I can feel Thawne's heart beating even more frantically than before. The energy surges and releases in a huge sonic wave._

 _The vibrations of Thawne's heart screech to a standstill._

* * *

Cisco jerked upright and his earbuds dropped out of his ears. He could still hear the overture playing faintly on his earbuds.

That was… what was that? That was a dream, but it was vivid as hell. The worst part was, it didn't scare him. If he saw Thawne in front of him, he would rupture his heart in a moment. No, he wouldn't, he would slowly vibrate it with smaller sonic blasts, to cause the most suffering.

"Cisco?" He looked up to see Caitlin standing in the doorway. His t-shirt and sweatpants hung off of her slight body, but didn't completely dwarf her. Her hair was tousled and parted in the back, as if she'd slept with her head in one position for too long. Her appearance was sleep-tousled, but her eyes were too wide and alert for someone who had just been sleeping.

"Hey." He pressed the power button on his phone to check the time. 3:17 AM. "Did I wake you up? Was I screaming or something?"

She shook her head. "I just wake up sometimes. Why would you be screaming? Did you have another bad dream?"

"Uh-" he hesitated, and she raised her eyebrows, like she was daring him to lie after their pact. "Yeah."

"Do you want to talk about it?" He nodded. She stepped out of the doorway and sat on the edge of his bed, folding her slender legs into a cross-legged position.

"It was Thawne," he began, and he saw her shoulders tense at the name, though her face remained sleepy and impassive. "From the aborted timeline, when he-" He held a hand up, shaking it from side-to-side in a poor imitation of the freaky-ass hand of death. Only this time, he didn't kill me." He tried to swallow, but his throat was dry. "I killed him."

"It was just a dream," she said gently. "And besides, he wasn't a good guy, Cisco. In fact, he was sort of a piece of scum. And he hurt you in a lot of ways. All of us, but especially you."

"I know." Cisco ran his fingers through his hair. "That's the thing. I wanted to kill him. I enjoyed it." He clasped his hands together and brought them to his lap. "If… if he ever came back… if I saw him in front of me today… I think I would kill him. Or at least hurt him." He could see Caitlin's eyes widening, so he fixed his gaze on his fingers as he intertwined them. "I want him to feel even a fraction of the pain that he caused me. I want to make him pay for what he did."

Caitlin was quiet for a moment, and then said, "I know how you feel."

"You don't need to say stuff like that, Caitlin. It's enough for you to just listen."

"No, I mean, I feel the same way." His head snapped up and he looked at her sharply, but now she was fascinated with her own hands. "I would hurt Thawne too. And _Zoom."_ Her hands clenched into fists, her knuckles white. "He tortured me. He made me doubt my own sanity, and everything I was. I want to make him suffer for that. Given the chance, I would put him through hell." She paused and squeezed her eyes shut, as if the very thought pained her. Cisco leaned forward and placed his hand on her knee, just to be touching her. "He constantly told me that he could see the darkness in me, that if I let it out, I could be a better version of myself. And I heard it so often that I believed it, but I don't think I needed that much convincing. I started to wonder, if I'm not a good person, then what am I?"

"You are a good person," he said in a low voice. She smiled ruefully.

"I'd like to think I didn't let the darkness win, but sometimes, I'm not so sure." She let out a shaky exhale. "I didn't know I could hate that much."

"Me either," he said quietly.

She nodded numbly, staring at her hands again. She looked so tired and defeated. He had only seen her like this a few times- without her pretenses to protect her. She rarely allowed herself to be vulnerable, even in front of him.

"You should go back to sleep," he said after a moment's pause.

"I don't know if I can." He raised his eyebrows, inviting her to elaborate. "I told you, I wake up sometimes. I'm not an insomniac or anything, I just-" she broke off. He waited for her to continue, but she was staring at her hands again. Her eyes were faraway and out-of-it.

"Cait," he said quietly, and when she didn't answer, he raised his voice. "Caitlin." She jumped and blinked quickly, like she'd spaced out. He wanted to ask her what was bothering her, why she hadn't been able to sleep, how long she'd been haunted by memories of Zoom like this. Instead, he just asked, "Are you up-to-date on _Jane the Virgin?"_

She looked up at him, taken slightly aback by the random question. "No, actually."

He swung his legs over the side of the bed. "Sounds like we have a date, then. You, me, and beautiful representation of the Latino culture."

She smiled and followed him out to the living room. He found the remote and settled onto the side of the couch. She sat down on the other side, and wrapped her arms around the pillow that she had been sleeping on. He turned the TV on and glanced over at Caitlin, her eyes still clouded with sleep and the corners of her mouth turned up with mild amusement at the punchlines. He had the strong feeling that he would do everything he could to protect her.

He noticed her eyelids slowly drooping, and then they fluttered open like she was trying to stay awake, but slowly closed again, and her head dropped to the arm of the couch. He reached for the remote and clicked the volume down so that the actors were reciting their lines in a low mumble.

 _I will never let anyone hurt you,_ he thought before he fell asleep.

* * *

 _"Cisco!" Caitlin sobs, and her eyes are wide, panic-stricken. "You need to leave, he's going to kill you-"_

 _"Don't worry, Caitlin," a low voice says, and I spin around to see Zoom, grinning widely and malevolently. "Killing him would take all the fun out of it. Instead I'm going to make him watch you suffer."_

 _His hand clenches on her upper arm and I see her flinch with fear and pain. Her pale arms are dotted with bruises, perfectly round bruises in sets of five._

 _His fingers._

 _His evil, dirty, fingers digging into her skin._

 _He doesn't deserve to touch her. He doesn't deserve her._

 _I feel my hands surge with energy and I'm stepping forward, no, flying forward, before he can hurt her anymore, before he makes her feel any less than he already has. I blast him out of the way, so that I won't hurt Caitlin, too, and then I have him frozen under my sonic boom. I can feel his organs vibrating and each one of his bones trembling._

 _I start by shattering his ribs, one by one._

* * *

An abrasive, screeching beep pounded against his skull. Cisco groaned and opened his eyes and realized that Caitlin was curled up against him. Her head was resting on his thigh and the rest of her body was folded up on the other half of the couch.

She looked so peaceful that he didn't want to disturb her, but the screech was grating against his head and shredding his nerves. His sleep-fogged mind tried to identify the source of the noise, but he was too tired. His eyes were seared by the dim light of the sun seeping in through the window blinds- it was morning. He realized that the intrusive beeping was Caitlin's phone, vibrating against the glass coffee table. He leaned forward, trying to reach it without moving, but it was several inches out of his reach. He scooted forward slightly and he felt Caitlin stir. _Damn._ He picked up the phone and read the name on the screen- Barry Allen. Caitlin's head had flopped over to the other side of the couch, but she was still asleep, so he slid his finger across the screen to answer the phone.

"Barry?" he asked, his voice croaking with sleep.

"Cisco?" Barry sounded surprised to hear him. "Where's Caitlin?"

"Asleep. She spent the night at my place." He crossed his arms, even though Barry couldn't see him, remembering that he hadn't seen Barry since before he broke Iris's wrist. That would be a fun conversation.

"She spent the night with you?" Barry asked, shocked, and Cisco realized his mistake in phrasing.

"I didn't mean like- it's not important. What do you need?"

"I was calling to see if she was coming in," Barry said. "We, uh, have a situation."

"What is it?" He sat up straight and jolted the couch slightly. Caitlin groaned softly and stirred again.

"Uh," Barry said. "Harry's here." Cisco felt his heart rate jump a little. "And he wants to talk to Caitlin, and he seems kinda pissed. When she's awake, can you tell her to come in as soon as she can?"

"Yeah, she's waking up now. I'll send her over soon." He hung up and placed the phone on the coffee table. Caitlin was sitting up, not yet fully awake.

"Who was that?" she asked blearily.

"Barry." He combed his hair behind his ear. "And, uh, Harry's here."

Caitlin's eyes widened. "What? I told him not to-" she scrambled to her feet, wobbling slightly on her tired legs. "What time is it?"

"It's-" He bent down and clicked her phone on. "7:41."

"I'm surprised Barry's there that early," she muttered, and picked up her folded clothes from last night, which were sitting on the coffee table. "I need to go talk to him." She turned and started towards the bathroom door.

"Hey, easy," he said. "You just woke up." And she had been sleeping next to him. He couldn't help but feel slightly heartbroken that their night together, strange and tiring as it was, was over and she was rushing off.

"I can't sleep all day," she said briskly. "And I want to give Harry a piece of my mind. I told him not to come here unless I told him to, and of course he didn't listen to me…" She shook her head. "You can stay here if you want."

"No." He shook his head. "I don't want to stay here and just… wallow. I need to do something."

She nodded. "Get ready, then. We'll leave in ten minutes."


	11. Chapter 11

Ten minutes later, he was in the passenger seat of Caitlin's Kia, and she was racing down Main Street like she was a getaway driver.

"Caitlin," he said when she plowed through a red light. "I think Barry and Harry will be okay for another twenty-five minutes. You don't have to break every traffic law to get there."

"It was yellow," she said dismissively. It most definitely was not, but her hard jaw and furrowed brow told him to drop it, so he did.

The car ride was uncomfortably silent. He could tell by the way her fingers clenched around the steering wheel that something was bothering her- from what he'd heard of her conversation with Harry and her brief comments that morning, she was less than thrilled that Harry was coming. But he didn't dare broach the topic, because she was so tense that if he said something to startle her she would probably flip the car over.

Cisco was grateful when the car finally jerked to a halt in the STAR Labs parking lot. He raised an eyebrow at her crooked parking job but didn't say a word.

Caitlin marched into the Cortex, her heels clicking defiantly, and Cisco hung slightly behind her, not wanting to be in her warpath. Barry and Iris were sitting next to the computers and Harry was standing by the white board. Everyone looked their way when Caitlin swung the door open.

"You," she said, pointing an accusatory finger at Harry.

He smiled, looking mildly amused. "Good morning, Snow. Ramon." He nodded at Cisco, but neither of them had a chance to say another word because Caitlin was _bristling._

"Don't 'good morning' me. I'm angry and you know why." She strode forward, advancing on him like a predator. "I _told_ you I had everything under control. I told you I could handle it and I didn't need your help, but instead you hop on over because apparently I can't be trusted to handle anything important and we always need a Harrison Wells to swoop in and solve our most complicated problems!"

Harry blinked. "I'm… sorry?"

"The hell you are," Caitlin spat, and the room fell silent. Caitlin rarely swore, so when she did, you knew she meant it. "I called you in to help because I respect you as a scientist and as a person, but apparently, that respect is one-sided." Harry opened his mouth indignantly but she cut him off. "Do _not_ try to say you respect me because if you did, you would have trusted me when I said I had it _covered!"_

Iris raced forward and grabbed Caitlin's arm. Cisco noted with a twinge of guilt that Iris had a plaster cast up to her elbow. "Give him a break," she said, looking Caitlin in the eye. "Let him explain himself."

"Thank you, Miss West." Harry cleared his throat. "I came because I thought maybe you _wanted_ help. Not because I thought you needed it. You're a hell of a scientist, Snow. I never doubted that."

Caitlin's eyes were still blazing, but she dropped her gaze to the floor and folded her arms. Harry's gaze drifted to Cisco and their eyes locked.

"There you are, Ramon."

Cisco felt his insides twisting together unnecessarily. "Hey," he whispered.

* * *

An hour later, Cisco was sitting on the end of the MRI machine, his head in his hands as he listened to Caitlin and Harry bicker their heads off.

"-an EEG is definitely necessary-"

"-you don't _know_ that-"

"We need to find out what he's seeing-"

"What if it's the placebo effect?" Caitlin argued. "This is why I didn't tell him to start with, because we risk confirmation bias. By making a big deal out of it, we might make him think it's worse than it is."

"Honestly, it's been pretty bad already, so I don't know how much worse it could be," Cisco said loudly, interrupting their arguments. "And honestly, I'm feeling pretty okay."

"As of 12 hours ago," Caitlin said flatly. "Just because you're feeling better doesn't mean we have nothing to worry about."

"And we have no idea what we're dealing with, which means we need to find out," Harry said forcefully. "Which is where an EEG comes in handy."

"Harry's right," Cisco said. "We need to know. I'm sick of not knowing."

Caitlin looked betrayed. "Cisco-"

"My body, my choice, right? I just want to know, and maybe what we find out will help us put an end to this." Cisco ran a hand through his hair. "I don't know if you're aware, but this is kind of my personal version of hell. So whatever we can do to get it over with, I'm on board."

Caitlin looked all kinds of not happy, but nodded. "Fine. Let's do this."

As it turned out, the EEG was completely unhelpful. "Brain activity is all normal," Caitlin said, flipping through the sheets. "I told you, it wouldn't work because he's not hallucinating."

"So maybe I'm all better," Cisco inserted.

"No," Caitlin said, at the same time Harry said, "Unlikely."

"It just means that whatever was causing your episodes isn't happening now," Harry mused. "So maybe… what if we try to-"

"If the next words out of your mouth are 'induce an episode', you can hop right back to your Earth," Caitlin said flatly. "You didn't see what those did to him. I'm not putting him through those again."

"It's his choice," Harry said, and they both looked at Cisco expectantly.

"Um…" Cisco fiddled with his hands uncomfortably. "Y'know. I'd prefer not to, honestly."

Harry sighed. "So what's our plan, wait until you go full Vader on us?"

"More like hope it doesn't happen again?" Cisco said, knowing how weak it sounded. "I'm sorry, Harry, I don't know what to tell you. I appreciate you coming all this way and you guys doing this for me, but…" He shrugged. "I really don't want to bring this on unless it happens again."

Harry glanced at Caitlin. "Fine. I'll stick around for a little while to see if anything happens, and if not, we pass this off as a fluke?"

"We should look over the various test results," Caitlin said immediately. "There might be something I missed. Maybe you can help me."

There was an awkward pause, and as if on cue, Barry poked his head into the room. "I'm not interrupting anything, am I? Cisco, I was wondering if maybe you wanted to take me up on my training offer. To help you get more comfortable with your powers and stuff."

"Yeah, I'd love that," Cisco said, and glanced quickly at Caitlin, who nodded.

"I'll come downstairs if we need anything," she said.

"Actually," Barry said, "I was thinking of going a little bit farther."

* * *

"Oliver? Really?" Cisco said when they were in Starling. "I mean, don't get me wrong, I love the guy, but isn't he the one who shot you in the back just to illustrate a point?"

Barry winced, and his hand migrated to his back, as if he were feeling the pain again. "That is still a sore point, but Oliver taught me a lot, and it really helped build my skills as a hero. I'm hoping he can do the same for you."

"You two realize I'm right here, right?" Oliver glanced at them from where he was hanging up his jacket. "I promise I'm not going to shoot you, Cisco. You don't heal fast like Barry does. I am going to put you through the wringer, though, so I hope you're ready."

"Trust me." Cisco pulled his hair out of his face and turned to face Oliver. "I was born ready."

Oliver smirked, impressed by his confidence. "Okay then." Cisco barely had time to blink before Oliver raced forward and _slammed_ him to the ground, each of his hands grasping Cisco's biceps.

"You're the super powered one," Oliver growled, his face an inch away from Cisco's. "Why'd you let me get away with that, huh?"

Cisco gasped for breath- the pressure of Oliver's mass was making it difficult to breathe. _What do I do? I don't want to hurt him._ Oliver's weight was pressing against his ribcage, almost crushing him. _But he has so much muscle mass, I might be able to get away with…_ He released a small vibrational wave, not a full-on blast, but just enough to push Oliver off of him. The other man tumbled away and hit the padded floor with a smack. Oliver leapt to his feet, but Cisco was ready this time. When Oliver lunged for him, Cisco opened a breach behind him, jumped in, and came out on the other side of Oliver. He was ready to blast Oliver down, but Oliver whirled around and slammed Cisco to the ground again.

"Nice trick, but you gotta think faster," Oliver hissed, and stood up, allowing Cisco to gasp for breath. "You have good instincts, Cisco. Trust your instincts. Don't let your insecurities hold you back. Don't hold _anything_ back." He offered Cisco a hand.

Cisco accepted it and staggered to his feet. "I don't want to hurt you."

Oliver chuckled darkly. "Trust me, you won't."

"Maybe, just to be safe, I could take a couple rounds with Cisco," Barry piped up from where he was sitting a few yards away. "You can do all the coaching, Oliver, but since I'm the one with super-healing, maybe it would be better if I did it so that Cisco can use his powers to their full extent."

Oliver shook his head. "Give me a couple more rounds, Bar."

They went at it again, and Cisco got some good moves in. He used his breaches and blasts to great effect, and he pulled a few over on Oliver, but every time, Cisco hesitated and found himself pinned to the mat again. After a couple hours of that pattern, Oliver helped Cisco to his feet again and clapped him on the back.

"Take five," he commanded. "We have a kitchen upstairs, go get some water and electrolytes."

Cisco nodded and headed upstairs, breathing heavily. Although he wasn't exactly winning at this, he hadn't killed Oliver, and he felt more comfortable in his own body than he had for the last few weeks. Oliver was intense, but it was actually really helpful. He forced Cisco to focus on using his powers in a positive way instead of being afraid of what he might do with them, because if he didn't, he got the wind slammed out of his sails over and over again.

He found a bottle of Gatorade in the upstairs kitchen, chugged the whole thing, and then went to the bathroom to splash some water on his face. It felt so good against his hot, sweaty skin. He looked up in the mirror, and for the first time that week, he wasn't filled with absolute disgust at the sight of his reflection. He didn't look weak or sick anymore. He looked stronger, older, confident.

He thought he saw his own lips curl into a smirk, but he passed it off as his own confidence coloring his perception of himself.

He went back downstairs to see Oliver waiting for him. "Let's get back to it," he said, and Cisco took his position on the mat. "Think on your feet this time. _Don't_ hold back."

"Ollie, maybe tone it down just a bit," Barry called, but Oliver shook his head.

"We're fine, Barry. Trust me, I know what I'm doing." He nodded at Cisco. "When you're ready."

Cisco took a running start at Oliver and he saw Oliver's arms go up, ready to grab him, but he was ready. He breached behind Oliver and blasted him to the ground. He was racing forward to send another blast when he felt a grasp on his foot. He glanced down to see Oliver's hand around his ankle and tripped and fell flat on his face. He felt Oliver's hands seizing his shoulders, and something in his brain snapped into place. _You're not going to get me this time._ He felt an unfamiliar energy take over his body and he pushed a monster blast of energy out of his body and sent Oliver flying away. Oliver's body hit the mat on the other side of the room with a dull thud.

"Cisco!" Barry was on his feet. "I think that was a little much. Is he okay?"

Oliver's limp form was stirring, but that was the least of Cisco's concern. His brain was still racing with adrenaline- _he was trying to kill me he didn't kill me I'm fine what did I do what am I doing -_ and his thoughts were slowly descending to reason, realizing that he might have hurt Oliver, when he saw a shadow out of the corner of his eye. He saw a mouth of white teeth flash a grin, and it filled his stomach with dread.

"Hey, buddy," Reverb said.

* * *

Caitlin stared at the computer in front of her blankly. "I'm telling you, there's nothing here," she told Harry. "I've looked at these over and over and there's nothing useful."

"Maybe you weren't looking for the right thing," Harry muttered.

Caitlin raised her brows indignantly. "Excuse me?"

Harry didn't look up. "All due respect, Snow, but we're different people, different scientists, and I have a _little_ more experience than you do."

"Yes, but I'm telling you, I've looked at all of these test results a million times," Caitlin said, exasperated. "If there was something there I would have seen it, unless…" She broke off.

Harry glanced at her. "Unless what?"

Caitlin stood up abruptly. "Unless I wasn't looking _at_ the right thing. I'm an idiot."

"I highly doubt that," Harry said, but Caitlin was hitting her keyboard furiously, pulling up exactly the document that she wanted.

"What's that?" Harry asked, glancing at the image on the screen in front of her. "Is that our EEG?"

"No." Caitlin stared at the screen in front of her. "This is an EEG I took a year ago when we were experimenting with Cisco's powers. This was right after he did a sparring session with Barry." She raised a finger at the screen. "Look at that."

"Imbalanced norepinephrine," Harry murmured, and glanced at her quickly. " _Way_ imbalanced. When we did our EEG, Cisco was relaxed, and he hadn't fought or used his powers recently. You took this right after he used his powers?" Caitlin nodded. "What does it mean?"

Caitlin felt an unpleasant, red-hot pit in her stomach. "It means we need to warn Oliver right now."

* * *

Cisco stared at Reverb, and he could feel his heart rate picking up. "Go away," he hissed. "Not now. I don't need you here."

Reverb shrugged. "Maybe not. But I think you _want_ me here."

"Cisco!" Barry grabbed his shoulder. "What were you thinking? You used way too much force on Oliver."

"It's okay," Oliver groaned, staggering to his feet. "He just got worked up. Which was kind of my intention, so-"

"You feel great, don't you?" Reverb said, and Cisco couldn't disagree with him. "Better than you've felt in a long time. This it how it feels to be in control. This is how. You don't want to go back to holding yourself back so you can fit into your place as the Flash's tech guy, do you?"

He didn't. He wasn't sure what he wanted, but he didn't want to stop feeling this way. He didn't feel scared to see Reverb, he realized, just slightly annoyed. He didn't need egging on. He had this covered.

"Let's just tone this down," Oliver was saying, clutching his right arm. "Do you want to switch out, Barry? I think I need to take a round off."

"Yeah." Barry glanced at Cisco warily. "Dial it back, okay, bud?"

Cisco nodded, ignoring Reverb in the corner of his eye. "Vibe versus Flash. Let's go."

Barry grinned tentatively. "On your count."

Cisco closed his eyes, preparing himself to use a controlled blast. _Not too much. Just enough to knock him to his feet, but not enough to hurt him._

 _But don't you want to hurt him? Don't you want to hurt him the way that he hurt you? Because he did hurt you. He killed Dante. He ruined your life._

 _He's the reason you're in pain, all of the time. Don't you want to make him feel a fraction of the pain that you've felt?_

 _I do. I do want to make him feel pain._

 _I want to put Barry Allen through hell._

He released a monster wave of energy from his fingertips, even bigger than the one he just released on Oliver. And this time, it was not an uncontrollable sensation, it was 100% conscious. Barry flew into the air like a ragdoll and smashed against the back wall. There was a loud, unpleasant, crack.

"The hell-" Oliver stood up and raced towards Cisco. "Okay, time-out!"

But this time, it was Oliver who wasn't fast enough. Cisco opened a breach and disappeared.


	12. Chapter 12

Caitlin's brain kicked into autopilot, blocking out the panic to do everything that needed to be done. Oliver didn't answer his phone, and neither did Barry, so she punched in Felicity's number while she watched Harry drag his hands through his hair. She explained to Felicity that Oliver and Barry were in danger and Felicity said she'd check on them. Then she called Wally, who flashed over to the lab and then flashed her and Harry to Star City, and then zipped back to Central to hold up the fort. When they arrived in the Arrowcave, the panic only intensified.

"Oh, no," she breathed when she saw Barry on the cot, eyes closed.

"He's just sleeping," Oliver said behind her in a low voice. "He was unconscious for a while, though."

She stared at Barry's limp figure. Felicity stood at a distance, watching pensively, and Harry was bent over with his head pressed into his hands. "Cisco," she said to Oliver. "He hurt you?"

Oliver nodded, expression unchanging. "He hurt Barry worse, though. He seemed a lot angrier. What happened to him?"

Harry's head snapped up. "What happened, Queen, was you antagonized him and pushed him off of the deep end!"

"Harry," Caitlin snapped. "This would have happened anyway. There's no need to assign blame."

Harry's face told her that he thought there was every reason to assign blame, but he kept quiet and started pacing instead. Caitlin turned to Felicity. "We need to find Cisco now, before he hurts anyone else."

"I'm on it," Felicity said automatically, and started typing furiously at her keyboard. A couple minutes later, she said, "He's not on any of the city's security cams. If he's in Star City, we don't have eyes on him."

Of course they didn't. Of course this had to be as damn hard as it possibly could. "We'll have to go back to Central City, then. I'll call Wally. Do you mind if we leave Barry here until he wakes up?"

She barely finished the sentence when Barry let out a low moan and rolled over. She rushed to his side and he blinked at her. "Caitlin," he said blearily, and then his eyes widened with panic. "Cisco- where is he?"

"We're going to find out," she said in the calmest voice she could muster. This only seemed to make Barry worry more, because he sat up quickly.

"This is all my fault. I shouldn't have brought him here, I shouldn't have fought him, I shouldn't have pushed him." He tore his hands through his hair. "I should have-" He broke off, and his eyes were dull with guilt. "This is all my fault."

 _He's right, it is,_ a cold, mean part of her brain said. _This is because of Cisco's grief, which is all because of Barry._ "No, it's not," she said firmly.

"But it is," he said softly. "I should have seen that he was struggling so badly." His eyes were shining and she knew he was beating himself up. Caitlin wished that she could tell him not to, but the cold, mean part of her brain was right. Barry caused this, in part. But so had she. She had been so busy worrying about her powers and her problems that she hadn't realized just how bad things were getting with Cisco. Sure, she had spent every moment at his side for the last three days, but it had started long before that. "I should have been a better friend."

"Me, too," Caitlin agreed. "But that doesn't do us any good right now. What we need to do right now is find Cisco. Can we do that?"

Something about her choice of words made a muscle in his face twitch. He stood up, face set with resolve. "Yeah. Let's find Cisco."

* * *

 _I can see everything from in here._

 _Every world, every timeline, every possibility._

 _I see a world where STAR Labs is thriving. I see a world where Caitlin is happy and safe. I see a world where my brother is alive. They are drastically different from the world that I know, but there's one common denominator that ties them together-_

 _Barry Allen is gone._

 _Arrogant, headstrong, reckless Barry Allen, who races through time and alters history at his whim. He'll change the past for himself- to be faster, to get his mom back, but he won't do it for me._

 _I guess I shouldn't have expected him to. I'm an engineer, we're kind of the "do-it-yourself" type._

 _And if you want something done right, you don't wait for Barry Allen to do it for you. You have to do it yourself._

 _Now it's all too clear to me what needs to be done. What I should have done a long time ago._

* * *

Caitlin stood in Cisco's workshop, taking in the horror she should have noticed sooner. On his desk lay a mess of diagrams and pictures, some hand-drawn and others computer-rendered. Pictures of lungs and brains and hearts. Depicting and calculating the vibrations of the human body. A notebook, pressed open with a paperweight, was covered in messy equations and numbers. Phrases like "beats per minute" and "breaking point" and "total failure" jumped out to her, and the room spun. She pressed her hands against the desk to keep herself upright.

"You're telling me none of you noticed this?" Harry asked incredulously. "Is that how much you've been neglecting him, that you don't notice painfully obvious red flags like _this?"_

Caitlin didn't respond to that, because there was nothing she could say, because she knew it was true. At least in part. Instead, she said, "He's been losing time. That could explain-" She broke off, and felt a wave of guilt. Barry was right. If they'd paid better attention to Cisco, maybe things wouldn't have exploded like this, but they'd all been so focused on their own problems and motives that they had forgotten their friends.

Namely, a friend. The friend who held everybody else up, who held the team together, who was strong so that no-one else had to be. Strong until he wasn't, until he couldn't be anymore.

"What does it mean?" Barry asked in a hoarse voice.

"You said when he blasted you down, it was more powerful than anything you've ever seen him do." Barry nodded. "He must have… he's been learning how to use his powers to… to hurt people." Her throat went dry. "To really hurt people. That's what he's been doing, that's why he's been blacking out and forgetting things…" It all seemed so remarkably clear now, but that provided no comfort. All she felt was angry at herself for not noticing, for failing him.

Harry picked up Cisco's notebook and paged through it, brow knitted with tension. His fingers paused on one page and he stopped dead. "You'd better look at this, Snow," he said in a low voice. He handed the notebook to her and she forced her reeling brain to concentrate.

 _1 billion beats per minute_ and then a complicated equation about mass and force, but it was all too clear to her what it meant. After all, she only knew one person whose heart beat at 1 billion beats per minute.

"He's going to kill you," she said in a hollow voice, and turned to face Barry.

Barry's face drained and he shook his head. "He wouldn't."

Caitlin pressed her hands against her forehead. "He wouldn't. But Reverb would." As soon as she spoke, Cisco's words from the last three days echoed in her head.

 _I wanted to kill him. I enjoyed it._

 _I didn't know I could hate that much._

 _Me either._

 _He screwed up our lives out of pure selfishness. He killed my brother._

"He wants to make you pay," she said, realizing. "You- you hurt him so badly. You're the reason for all of his grief." There was no accusation in her voice, she was just talking through it, but Barry still looked like she'd kicked him in the gut. "He wants to hurt you."

"He wouldn't," Barry repeated, shaking his head. "Cisco couldn't do that. He's not Reverb. He couldn't do that."

"Maybe not," a loud, harsh voice drawled, and Caitlin's blood froze in her veins. "But I am Vibe, and trust me, I _can_ do that. And I will."


	13. Chapter 13

Caitlin turned around slowly, feeling terror swelling in her chest. Cisco stood in the doorway, but he was barely recognizable as Cisco. He was still dressed in his own clothes- a vintage Jurassic Park t-shirt, blue jeans and that one black jacket he always wore -and his goggles and gauntlets were the same as they'd always been, but he was markedly different. His posture was strong, powerful, and his lips curled into a smirk, exuding superiority. She didn't know whether to be terrified of his power or heartbroken that he had fallen so far. She just felt sick to her stomach and her throat was too dry to speak.

Barry spoke instead. "Cisco, you don't have to do this," he said in a low, careful voice.

Cisco tilted his head. "You didn't have to save your mom, but none of us are perfect." Barry swallowed and his eyes dampened. "You had to think this would catch up to you eventually, Barry. Every action has an equal and opposite reaction. You wrecked my life, and now I'm wrecking yours." He stepped forward, and gosh, he even walked differently. Caitlin backed up and felt Barry and Harry moving beside them, but she knew that he was backing them into a corner.

"This isn't you, Ramon," Harry said calmly. "Your brain chemistry is being affected by your powers. You're not yourself."  
Cisco smirked. "And thank goodness for that. I always hated that guy. You know, all this time, I've been wondering why I couldn't master my powers. And I finally figured it out- it was you." He advanced on them like a predator. Caitlin backed up and bumped into Harry. They were running out of space, and out of time. "It was all of you. I depended too much on you, but you're all inferior. I'm the most powerful meta in the universe. I can manipulate the very strings on which our world sits. I can peel away the fabric of dimensions in time. If I want to harness my power, there's no place for human emotion and connection. That's always been my weakness."

Barry laughed weakly. It sounded like he was in pain, like someone had kicked him in the diaphragm. "Do you hear yourself? You're doing the cliche evil villain monologue. Come on, Cisco, you're better than this." He stepped forward, shielding Caitlin with his body. She about shoved him out of the way until she noticed his hands behind his back, one hand curled around the other wrist. _The cuffs._ Caitlin glanced at the cuffs on her wrists and her throat tightened with panic. If she took them off, she might lose control, and then they wouldn't be any better off.

"See, I realized that, too," Cisco said. "I _am_ better than this. I'm better than being your scapegoat."

Caitlin glanced at Harry, who had noticed Barry's subtle gesture. He locked eyes with her and widened his eyes as if to say _Go on._ She glanced back at him and shook her head. There had to be another way. Harry glanced at Cisco and then back at Caitlin. _Please,_ he mouthed. She shook her head. She could help, but not like that.

"Cisco, listen to me," she said suddenly, and shoved Barry out of the way.

"Cait," Barry hissed, and shook his head, but she ignored him.

"I know you're hurting. I know you're in pain, but this won't make anything better." Cisco tilted his head in her direction and she could tell he was listening, so she rushed on. How had she gotten through to him before? _Fictional analogy. Think of something nerdy, come on Caitlin, anything... "_ You're Anakin Skywalker, remember? The force is strong. You don't want to become Vader, I know you don't. This isn't who you are."

"Maybe not." Cisco said softly, and for one breath-baited moment, Caitlin thought she had gotten through to him. "But do you remember how Anakin became Vader, Caitlin? He was broken. So broken beyond recognition that there was no going back. He could never be Anakin Skywalker again, even if he..." His voice faltered. "Even if he wanted to." Caitlin's heart wrenched in her chest. "And that's all thanks to you, Barry. _You_ broke me. You shattered my heart when you _killed my brother."_ His voice was hard and harsh, but his lower lip trembled ever so slightly. "The least I can do is return the favor."

"There's nothing I can say that will make Dante come back," Barry said softly. "I'm so sor-"

"You're sorry?" Cisco laughed harshly. "You keep saying that. Sorry's not enough. Nothing is."

What followed happened so fast that Caitlin barely had time to register it. Cisco blasted Barry to the ground and Harry shouted, "Snow, the cuffs!" and Caitlin scrambled to take them off.

Cisco released another wave and Harry crumpled to the floor and Barry bounced back up and raced towards Cisco but then a breach opened behind them and Cisco and Barry fell into the breach and vanished.

Caitlin rushed to Harry's side and pressed her fingers against the side of his neck. His pulse was faint, but it was there. She pressed the panic button on her phone and prayed that Wally would know what to do. Then she raced down the hall towards the cortex.

* * *

Cisco's heart was racing in his chest, too fast, too heavy. _Ba-dum, ba-dum, ba-dum._ He felt like he was watching himself from outside his body, like he was floating, like he wasn't really there. The power surging through his body made him feel alive, but in the worst way possible. He felt like a live wire, surging and seizing and sparking. He felt like a grenade in the split second after the pin was pulled but before the explosion.

He stood on the roof of STAR Labs, and although it wasn't the tallest building in the city, it felt like he was standing above the stratosphere. His heart hurt, physically hurt, like there was a shard of glass stuck in it. His brother was dead and he would never see him again. He had lost so much because of this agonizing life he lived, because of Barry, who he desperately wanted to hate but couldn't, and that somehow made him hate Barry more.

Barry's eyes were wide, his mouth opening and closing in an ardent plea for mercy, but it was lost under the blood rushing in Cisco's ears. Barry had caused so much pain, and not just to him, but to everyone around him. Everything Barry Allen touched burned, and Cisco wanted him to pay for it, so badly. But the tears in Barry's eyes pricked at a deeper part of his soul, a part of him that was hidden deep under the layers of pain and anger. _Star Labs forever. The universe wants us to be bros._ The memories only made him hurt more. That Barry was gone. The Barry that returned from Flashpoint was not the same Barry who sat hunched over on Joe's porch after his father's funeral. That was the Barry that Cisco knew, the one that he loved, but he was lost to the ripples of the multiverse. This was the arrogant man who treated time as his toy and their lives as a game. Barry Allen deserved no mercy.

Still, he hesitated. He didn't have to kill Barry. He didn't even know if he had it in him. He looked at Barry, cowering on the ground, tears streaming down his face. He didn't move because he knew that Cisco could shatter his organs with a flick of his wrist. Maybe, Cisco thought, he had already suffered enough. Maybe leaving Barry to deal with the consequences of his actions was penance enough.

But this wasn't about penance, it was about revenge. It was about the gaping hole in Cisco's chest that couldn't be mended. It was about the world of power that he felt at his fingertips. He knew if he gave himself over to it, the pain would stop. Reverb- the real one, not the one in his head -was so _empty._ He never felt anything, he never regretted anything, he just reveled in his own power. He never had to feel pain, because he never felt anything. Cisco wanted that so badly, because right now the pain burned so badly that he couldn't bear it. He had to give himself over to his power entirely, to let it consume him, and this was how. _Your human connections hold you back from your full potential._ If he killed Barry Allen, he could never be Cisco Ramon again, because Cisco Ramon would never be able to live with himself, no matter how angry and heartbroken he was. He had to hand himself over to Vibe. He had to become Vader.

He stared at Barry's red eyes, and Barry's mouth stopped moving. The corners of his mouth turned up hopefully, like he thought his meaningless chatter had somehow broken through the catastrophic cacophony consuming Cisco's brain. _You are so small,_ he thought, almost pityingly. _I can escape this pain because I am the universe. You can never escape it._

 _Maybe I'm doing you a favor._

He closed his eyes and carefully searched through the vibrations until he felt Barry's unnaturally fast heartbeat. Just one controlled vibration would be enough. He didn't have to make him suffer.

But he could. Maybe he needed to. There was no doing this halfway.

"Cisco!" His own heart broke into a thud. _Don't look at her. Don't think about her, don't listen to her._ He could justify killing Barry Allen, but he could never, ever hurt Caitlin Snow. He loved her, although he wasn't sure how.

This was why he hadn't killed Barry yet. Not because of Barry, but because of Caitlin. Caitlin was love and warmth and hope, encapsulating the only good things about his life. He had pinned all of his hope on her for so long, but there was no room for hope among power and apathy. He had to give her up.

He stared down at the ground, at his once-no-more best friend, begging for his life. He stared ahead at the woman he loved, shaking her head, calling out to him, begging him to stop.

 _Ba-dum, ba-dum, ba-dum._ His heart raced and he looked at Caitlin again, and back at Barry.

 _I'm so sorry,_ he thought, and as he looked at Caitlin, the one warm part of his heart broke for her.

He turned back to Barry and closed his eyes.

Caitlin felt numb all over. Barry was curled into a ball on the ground, grasping at his chest over his heart and trembling. Cisco stood over Barry, his hand raised as if he were crushing Barry's heart under it. He was right, he was broken beyond recognition. How could she get through to him if he wasn't even Cisco anymore?

"Cisco, stop," she yelled, her voice hoarse and raw. He turned his head and froze.

"Please," she begged. "Please don't do this. Not for Barry, not for me, for you. The universe screwed you, and maybe Barry did, too, but you don't have to let that define you." Cisco's hand lowered. "You are so much better than you are right now. If you kill Barry, you're killing Cisco Ramon, too."

He stared at her, but with those goggles on she had no idea what he was thinking. "I know," he said in a strange, faraway voice. "Why do you think I want to do it?"

Her heart broke and she felt her eyes stinging. "Take those goggles off," she shouted. He stared at her. "I'm serious. If you're going to kill Barry, look me in the eye first. Look him in the eye." He looked back down at Barry. "Take them off, Cisco!"

Slowly, slowly, he raised his hands, and removed the goggles from his head. He turned to face her and their eyes locked. After removing his goggles, he somehow looked even more unrecognizable than before. This man was a stranger to her.

"You don't want to do this," she said. "I know you don't."

"That's where you're wrong," he said coldly.

"You're a terrible liar," Caitlin said. "Whenever we find spiders in the lab, and I want to kill them, you scoop them up on a piece of paper and put them outside." His face twitched and his hand lowered. "You don't want to do this."

He stared at her, and she saw the mask begin to crack. His lower lip, trembling slightly. "This is what has to happen."

She shook her head. "No. This is over the line. This is horrific, and you know that."

"I have to do this," he said, and his eyes welled up. "I have to do this. This is the only way."

"No, it's not." She stepped forward, cautiously, and when he didn't move, she stepped forward again. "There's always another way. End all of this and we'll figure it out together. Please."

Cisco glanced at Barry again, and then looked at Caitlin. A tear tracked down his cheek and the mask crumbled. She had seen Cisco sad and angry and heartbroken and depressed, but this was something else. His face was glowing like the heat from an atomic shockwave. He was sparking and flaring like a supernova, and it broke everything in her to see him that way.

"Come on," she murmured. "You are stronger than this."

"No, I'm not." He shook his head.

"Yes, you are," she breathed. "If you can't believe that right now, I will believe it for you."

He shook his head, blinking away tears. "That's not who I am anymore."

"That's okay. It's okay to change. Sometimes we have to." She extended her arm, holding her hand out. "Come on. Let's end this, Cisco."

He shook his head again, just a slight side-to-side movement. "I don't- I can't-"

"Shh," she murmured. "You don't have to fight so hard." She reached forward and touched his shoulder. He flinched under her touch and squeezed his eyes shut.

"Please don't," he whispered.

"No." She stepped closer and touched her hand under his chin, cradling her face. He tilted his head against it, as if he were trying to memorize her touch. He opened his eyes, and she could see something sparking in them. He pulled away and looked at her regretfully.

"That is why," he murmured, "I have to do this."

She stared at him. "Cisco-"

He raised his hand and closed his eyes.

Caitlin's brain switched gears instantly and started racing through strategy, operating in the fraction of a second that it had. There was always another way, just like she told Cisco. But when one way doesn't work, sometimes you need to do what has to be done. And it broke her heart to pieces, but she was more than willing to do what she had to do. She couldn't let Cisco do this- not just to Barry, but to himself.

 _Snow's strong,_ Harry's voice said in her head. If that ever was going to be true, it had to be now. Sometimes being strong meant doing what needed to be done, even if it was the opposite of what you wanted.

She ripped the cuffs off her wrists and tossed them to the ground. She held out her hand and ice spiraled from her fingertips.


	14. Chapter 14

_It's dark and cold, colder than I was before._

It's August 9th, 2016.

Except this time- this time it's not just a delusion. I feel the details of August 9th, 2016 with painful realism because this time, it's not just an echo of reality or an outcome that could have been. This time it's right. This time, I'm exactly where I'm supposed to be.

 _Where I was._

 _I'm in the passenger seat of Dante's Volvo. He has one hand on the steering wheel, and he's going way faster than he should. We're arguing, but the words don't matter. All I know is what's coming, and now that I know I hate myself for not noticing the blue Jeep speeding towards us on the highway to hell. The scene plays out with painful accuracy. It is because of me that Dante turns his head to defend himself. Because of me that Dante looks up too late to see the Jeep, feet away from his dashboard, and swerves at the last second._

 _We are airborne. The car slams against the ground, and it shakes every bone in my body. My head is screaming and my arm is twisted and pinned beneath my body. That doesn't matter. Dante's form is pressed against the steering wheel, and his head is tilted to the side at an angle that makes my stomach turn._

 _I can barely see or think, because my brain is yelling at my body to go into shock because if I see much more of this horror, I won't be able to survive it. I can't breathe. I'm suffocating. My stomach is acid and when I see the blood trickling down Dante's neck I feel bile rising in my throat._ Shut down, shut down, _my brain signals frantically, but my body won't let me, it's like it's forcing me to stay alive to punish me…_

 _I hear footsteps approaching and the door clicks open. I start shouting and crying and begging,_ please please help my brother is dying.

 _I feel myself cross over the line from reality. I know what's supposed to happen next, but it doesn't._

 _Instead, I hear Caitlin say, "Get up."_

Cisco was limp on the ground, crumpled on top of the pathway of ice. Caitlin bent down beside him, and the cold part of her brain whispered, _put him out of his misery. No,_ she whispered back, and pressed her fingers against his neck, feeling around for the carotid artery. There he was.

"Caitlin?" She turned her head and saw Barry, standing up now. His face went ashen. "What did you do?" he shouted, and raced towards her. He crashed to his knees and grabbed Cisco's shoulders, and Caitlin saw the heartbreak and fear all over his face.

"No, it's okay," she said, and when he didn't hear her, grabbed his shoulders. "Barry!" she shouted, and he stopped crying. "I just- he's just knocked out. I was saving your life."

Barry stared at her, and swallowed hard. "Oh," he managed, and touched the hair above his ear. Caitlin grabbed at her hair- blonde.

"Oh," she whispered, and Barry stared at her wildly, as if he weren't quite sure whether to let his guard down. "Are my eyes-"

"Not anymore," Barry said, and seemed to relax. "You didn't let her out. You're still you. You controlled her."

"I found the strength I needed," she said, looking down at Cisco. "I had to."

Barry nodded. "You saved both of us."

Her throat tightened. "We need to get him down to the med bay," she said automatically. Barry nodded and scooped Cisco up in his arms.

 _Caitlin stands by my side, and I feel her eyes watching me. I stare at Dante's car, upside-down and crushed._

 _"This is the first step," she says. "Recognizing how you feel, I mean."_

 _"I didn't-" My stomach hurts. "I didn't realize I felt this guilty."_

 _"That's because you didn't let yourself think about it," says Caitlin. "You blocked it out and pushed it down, so it festered."_

 _"It's not just me," I say. "I blame him too."_

 _"That's true," she says. "And you can be as angry at him as you want, but make sure it's because you blame him, and not because you blame yourself."_

 _She walks toward the Blue jeep, parked in the middle of the road. I follow her and watch as she opens the driver's side door. Barry sits at the wheel, hands clenched over it, a tear streaming down his face._

 _"I do blame him," I say. "It's his fault. He caused this. I know why he did it, but he's not the only one who's lost someone. You didn't do anything like that when Ronnie died. I could have vibed back and saved Dante myself, but I didn't."_

 _"No," she says. "He made a mistake, and we're all dealing with the consequences. It's not fair, but he can't change it. None of us can."_

 _"He wishes he could," I say, staring at the tear on Barry's cheek._

 _She nods. "You don't have to let that be enough, but you don't have to let it ruin you, either."_

 _"It's hard," I say. "It hurts so much."_

 _She nods, and glances at my chest. "Maybe it would help if you took that out."_

 _I glance down and see a twisted piece of metal embedded partway in my chest, surrounded by a large crimson stain. "It's in too deep," I say. "It's right above my heart. I could die if I try to take it out."_

 _"That's a risk you're going to have to take," Caitlin says._

Caitlin stared at the heart monitor anxiously. His vitals were too low, too slow.

"What did you do, exactly?" Barry asked in a hoarse voice.

Caitlin shook her head. "I just knocked him out," she murmured, but she knew that something was wrong. He was taking too long to wake up.

The moment she thought that, the heart monitor started beeping and Cisco started seizing. Barry leapt to his feet.

"Do something," he begged.

"Hold him down," Caitlin instructed, and they did. She turned to her shelves and filled up a syringe. She was about to inject him when she heard the dull tone of the flatline.

"Crash cart," she commanded, her voice level. Barry grabbed the crash cart and pulled it over to the cot. Caitlin vaguely heard voices and she supposed that Wally and Harry must be there, and maybe Iris, but she shut it out. She ripped Cisco's shirt off and grabbed the paddles.

"Clear," she said, to no-one because no-one was listening, and pressed them against his chest. The tone of the flatline droned on. She leaned over him and started compressions.

 _"Caitlin, I'll die," I say. "I'll bleed out. You should know that."_

 _She nods. "I do. I also know that it's puncturing your aorta. You won't survive if you leave it in, either."_

 _"Why does it have to hurt so much?" I ask, staring at the blood on my chest._

 _"It doesn't," a voice behind me says. "Like she told you, there's always another way._

 _I recognize the voice before I turn around. Dante stands behind me, whole, unharmed._

 _"Vamonos, hermano," he says quietly. "You can save me. Save me, and it will stop hurting, I promise."_

 _I stare at my brother with tears in my eyes. "You're dead," I say shortly._

 _"I don't have to be," he says with a smile. "You can save me. Dios me llevó lejos, pero_

 _tú puede tomarme de nuevo."_ God took me away, but you can take me back.

 _I step forward and take in my brother- his face, his smile. Taken too soon._

 _Dante smiles at puts his hands on my shoulder. "Mírame," he whispers, and touches his fingers to my chest, just above the wound. I feel it numbing as the pain ebbs. "No tiene que doler," he says. "It doesn't have to hurt."_

 _I look up at my brother- my_ brother _-and remember those strong hands protecting me from bullies in grade school. I remember that rare smile he smiled whenever he was proud of me._

 _I turn back to see Caitlin. "It doesn't hurt anymore," I say._

 _She nods sadly. "I know. That's why."_

 _I look down and see that the blood around the wound has turned dark._

* * *

When Cisco's heart finally started beating again, Caitlin almost cried with relief.

Instead, she hooked him up to an oxygen tube and treated his wounds, and then tended to Barry and Harry. When there was no-one left to take care of and she was still on her feet looking for something to do, Iris forced her to sit down and drink a mug of tea. She couldn't stomach more than a few sips, because now that she wasn't moving and working, her brain had room to process everything that just happened, and it made her feel sick to her stomach.

"What's wrong?" Iris asked, seeing Caitlin's white knuckles on the handle of the mug. "You saved him."

She shook her head, staring at Cisco's form, still save for the subtle falling and rising of his chest. "I don't know if I did. I don't think I did the right thing. I should have talked him out of it, not…" She twisted her fingers in her hair. So very blonde. "When he wakes up, he might be as bad as before, or worse. I didn't talk him down, I didn't make anything better, I just… stopped him." She felt her heart skip. Maybe she'd let her violent side take over. "I thought I needed to stop him, but I think..." she swallowed, hard. "I think maybe that was her."

"Caitlin." Iris leaned forward so that they were eye to eye. "You did everything you could to help him. Pep talks can't always save the day. Somebody has to make the hard decision to put their foot down, and you did. You're stronger than all of us, and that is why Killer Frost-" She said the name deliberately, enunciating every syllable, as if to let Caitlin know that she was not afraid to say it. "-is _never_ going to take over." She squeezed Caitlin's shoulder briefly. Caitlin smiled at her absently. "If your hair bothers you so much, I know a great stylist downtown."

Caitlin realized that she was holding her hair tightly inside of a clenched fist. "How bad is it?"

"It doesn't _look_ bad," Iris said diplomatically, and at Caitlin's skeptical expression, "Honestly, it's cute. Kind of playful. I have a compact mirror if you want to see." Iris fished around in her purse and handed it to Caitlin.

Caitlin opened the compact and stared at herself. She wasn't all the way platinum blonde, but the blonde sections were larger and the rest of it was far lighter than before. Her stomach flipped over and she shut it quickly.

"Caitlin, it's just hair," Iris reminded her. "It doesn't mean anything. All that matters is _you,_ and today, you showed that ice bitch who's boss."

Caitlin smiled at her gratefully, and then saw Barry out of the corner of her eye, leaning against the wall, face still pale. Iris noticed and silently stood up to go talk to Harry. Caitlin turned in her chair to look at Barry. He didn't acknowledge her for a moment, and then spoke.

"Did you mean what you said? When you were talking to Cisco, you said that… that I screwed him over."

She blinked at him. "You _did,"_ she said bluntly.

He winced. "I know I did. I just didn't know that you agreed."

She felt a twinge of guilt that was quickly stomped out by indignance. "You _did_ screw him over, Barry. You had your reasons, but he has every reason to be angry at you. This was a little extreme, but he is _justified_ in his anger, and it's going to take a lot for you two to heal that."

"I'm trying," he said in a frustrated growl. "I know I messed up. All I can do is try to fix it."

"You can't," Caitlin said, and he got that wounded look again. "All you can do is be better, but you can't make him forgive you."

Her gaze drifted to Cisco, young-looking in his sleep. Barry moved and she was conscious of him sitting down next to her.

"I can't believe we let it get this bad," he murmured.

"Me either," Caitlin said softly. "I guess sometimes it has to get worse before it can get better."

* * *

 _I stare at the dark blood on my chest. "What's happening to me?"_

 _"That's what poisoned blood looks like," Caitlin says. "That's the only way for it to stop hurting."_

 _I shake my head. "I don't want this."_

 _"Cisco, once you do it, you won't care about that anymore," Dante says. "You might regret it now, but once you make the decision, you won't regret it a bit. You won't feel a thing."_

 _It's tempting, so tempting. I look back at Caitlin._

 _"The pain is unbearable, isn't it?"_

 _It is. It always is- I'm used to pain. I've been in pain since Dante died._

 _Maybe it's time to stop._

 _"Lo siento, hermano," I whisper, and turn my back on Dante. I grasp the shrapnel and yank it out, and I collapse to the ground. Caitlin is holding me in her arms and she smiles down at me._

 _"I'm so proud of you," she says. "I knew you could. I told you you were strong."_

 _"I'm bleeding," I gasp. "I can't- I can't breathe."_

 _She nods. "That's how you know you're human." She presses her hand against my chest and then lifts it up so I can see it. Her palm is stained scarlet. "This is how you know you're alive. Life is pain. You have to feel pain to be human. And despite your best efforts, you still are."_

 _I stare at her and pull away. I suddenly have the strength to stand on my feet, and I do. Caitlin stands with me._

 _"You can come back," she says. "But when you do, it will still hurt. It won't stop hurting."_

 _"No," I say, and stare at the blood on my chest. "It won't."_

* * *

Cisco was awake before he opened his eyes. He heard low voices murmuring around him and the faint beep of a monitor.

"Cait," he murmured, and opened his eyes. Caitlin and Barry sat on either side of him in chairs. Iris stood behind Barry, and Harry leaned against the wall in the background.

"Cisco!" Caitlin leaned over him, her eyes wide with relief. "You're- you're awake."

"Finally," he said, and tried to sit up. Caitlin grabbed his shoulder firmly and pushed him down.

"Don't try to sit up," she said unnecessarily. She glanced at him uncertainly. "How do you feel?"

"I-" he blinked, and then felt a flood of overwhelming guilt as everything came back to him. "Barry," he whispered.

He felt a strong hand on his other arm. "I'm right here," Barry said in a hoarse whisper. "I'm okay."

"You scared us, Ramon," Harry said from the wall. "Welcome back."

Cisco pressed his head against the pillow. "My head hurts," he said.

Caitlin nodded. "You hit the pavement hard when you slipped on the-" She faltered. "On the ice."

He grabbed her hand. "Thank you for stopping me. Are you okay?"

Her lips curled in a soft smile. "I think so."

"How do you feel?" Harry asked. "Are you hallucinating still?"

Cisco looked around the room carefully for any sign of Reverb. "No." He glanced down at his hands- not shaking. "I feel pretty normal, actually."

"That's ironic, seeing as you just died," Iris said from behind Barry.

"I died?" He looked at Caitlin quickly, and she nodded confirmation. " _Again?"_

"You should stop doing that," Caitlin said, and her lip trembled. He wished he hadn't seen that. "You've filled up your quota."

He stared at the ceiling, feeling overwhelmed. "Barry," he said without looking at him. "I'm sorry that I tried to kill you. But I still don't- we aren't-" He trailed off.

Barry nodded. "I know. That's okay. We can talk about it later, or not at all."

Cisco shook his head. "We _have_ to talk about it. Just not… just not right now."

He stared up at the ceiling and tried to numb the pain in his chest. He heard Caitlin say, "He needs to rest," and Barry and Iris trailed out of the room. Harry lingered at the wall a moment, nodded at Cisco fondly, and then ducked out of the room. Only Caitlin remained.

He pressed his fingers against his chest, expecting to find a piece of shrapnel or a wound, but there was nothing there. He rubbed his fingers against the phantom pain.

Caitlin noticed. "Does something hurt?" she asked in her doctor voice.

Cisco nodded. "Everything." Caitlin seemed to catch his meaning, because she sat down on the edge of the cot and grasped his shoulder.

"I'm sorry," she said. "I'm so sorry. I didn't realize you were in that much pain."

"Neither did I," Cisco said. "That doesn't mean that what I did was okay."

Caitlin shook her head. "You were in pain. None of us helped you."

He shook his head. "It's not just that. I saw my dark side, and I liked it." He paused. "Maybe I didn't like it, but I liked it better than the alternative. I thought it would be better than feeling weak, but I couldn't even do it. I hated Barry. I think I still do. But I still couldn't kill him."

"That's because you're a good person." Caitlin rubbed his shoulder. "You always will be. It's just who you are."

"I could have been like him," Cisco said. "Reverb, I mean. He didn't care about anybody. That's why he was so powerful, because there was nothing else there. I was so close to letting go."

"I've been there," Caitlin said softly, and tilted her head to look at him. "The only thing that stopped me was… you." She gazed at him and he saw something indefinable in her eyes. "What stopped you?"

"You did," he said instantly, and she raised her eyebrows at her assuredness. "Barry's hurt me badly enough that I could rationalize it, in my head. But there was no rationalizing it with you. It wasn't even an option. If I let go of pain, I would have to let go of you, and I can't do that."

"You don't have to let go of me." She squeezed his arm. "I'm right here."

"I know," he said, and pulled away slightly. "What am I going to do about Barry?"

Caitlin sighed softly. "I don't know. I don't know how to fix that."

"You can't," Cisco said bluntly. "I don't know if I can."

"You don't have to," she pointed out.

"He's trying. He feels bad."

"That's not enough."

"No," Cisco agreed. "Maybe I should give him the chance to try, though."

"But not for him," Caitlin said. "For yourself."

They were quiet for a long time, and when Cisco realized she wasn't going to leave, he rolled over to the side of the bed. She understood the invitation and slid onto her back. They laid there on the cot, shoulder to shoulder, staring up at the ceiling.

He rolled over onto his side to look at her. "You haven't forgiven him either, have you?"

She stared at him for a moment, chewing her lip, and then shook her head slowly. "No. Not yet. But I'm trying, because I know that it'll just hurt me."

"It hurts you more than it hurts him." He remembered the shrapnel in his dream.

She nodded. "I know. That's why I stopped you. I couldn't stand to see you do that to yourself, because I know that's not who you are."

He looked at her and felt his heart skip. She looked as exhausted as he felt.

"Cait?"

"Yeah?"

"I'm really tired."

"Me too." She laid her arm over his shoulders and pulled her to him. "Let's rest. We'll feel better when we wake up."

He closed his eyes and nestled his head against her shoulder. He felt her heart beating against his, the rise and fall of her chest, her breath on his nose.

"Cait?"

"Hm?"

"Things aren't going to go back to normal, are they?"

"I don't think we have a normal to go back to, but maybe that's okay. I'm not sure yet."

"I promise I won't do that again. I mean, I still… there are still things I need to work through, with Barry, with myself."

"That's okay."

"I know. I just wanted to say… thank you. Not just for saving me, but for being what you are to me for so long. You wouldn't have been able to get through to me like that if you weren't… you mean everything to me."

"Everything?"

"Yeah. Is that okay to say?"

"More than."

"Thank you for giving me something to hold on for."

"Thank _you._ For being the strength I needed."

"How's that again?"

"Remind me to tell you when I'm not so exhausted.

"Mkay. Let's get some… whoa. Those- those are your lips."

"They are indeed."

"I have lips too."

"I'm aware. They're very nice ones."

"I feel like this isn't the right time for this."

"No, it's not."

"But maybe soon?"

"Soon."

He didn't feel instantly okay. But maybe it only took an instant to realize that he would be.


End file.
